Vacuum Evaporation of Metals for Shadow Casting

Abstract

Various metals in common use for shadow casting were evaporated in vacuo and their empirical evaporation efficiencies were compared with a weight method and with multiple-beam interferometry. A nomograph and appropriate correction factors were developed for rapid and accurate thin-film thickness predictions. Use of the evaporation formula to determine thickness gave values ranging from one-half to two times as much as those obtained by multiple-beam interferometry. Individual variations are believed due to alloying characteristics and physical properties of the evaporated film. A method is presented which enables thin-film thickness predictions with a high degree of accuracy for the materials used.

Layering Phenomena in Colloidal Suspensions

“…Since the clay particles had a preferred orientation on the carbon film, a value for the average thickness was obtained by measuring the shadow cast by the particle. This value, corrected for the film thickness using the method described by Rosauer and Wagner (1966), was found to be 200 ,~ with a maximum variation of • The clay particles exhibited excellent hexagonal habit and therefore the plate diameter could be obtained by use of Feret's statistical diameter.…”

Characterization of ammonium polyuranate powders from a continuous precipitator

“…After obtaining the desired crystallite size measurements, the standard technique of metal shadow casting (27) was used in order to obtain the particle thickness and therefore a volumetric shape factor for the crystallites. For most of the samples the TEM micrographs revealed several crystallites standing on edge.…”

Late Transition Metals, Metal Halides, Metal Oxides, and Metal Sulfides (Group VIII)

“…37 Field evaporation methods 25 and various reports of evaporation for shadow casting scanning electron microscope samples have also been published. 38 And in 1963, Liebl and Herzog reported an important discovery regarding 82 5 References 2, …”