Abstract

This paper deals with experimental observations of the reflection and transmission characteristics of freshly evaporated films of an Al-Mg alloy (Al 95 percent, Mg 5 percent). Appropriate apparatus was arranged inside of an evaporation chamber so that measurements could be made during and after the deposition of the metallic film. Three types of changes in the reflection and transmission coefficients for white light were observed to take place. (1) The first type (occurring at pressures of 10⁻⁴ mm or less) consists of a small rapid decrease in reflectivity and increase in transmissivity. No further effect was observed to take place in the vacuum. (2) The second type occurs during the admission of air or other gases into the vacuum chamber. Similar to the first change, this consists of a decrease in reflectivity and an increase in transmissivity. (3) The third type takes place very slowly and over a period of several days. The final value of the reflection or transmission coefficient is approached asymptotically. In a typical case the magnitudes of the three types of changes for a film having an initial reflection coefficient of 58 percent were observed to be 8 percent, 5 percent, and 10 percent, respectively; and for another film having an initial transmission of 35 percent were 5 percent, 8 percent and 5 percent.

© 1937 Optical Society of America

Apparatus for the Measurement of Vacuum Ultraviolet Optical Properties of Freshly Evaporated Films before Exposure to Air

R. P. Madden and L. R. Canfield
J. Opt. Soc. Am. 51(8) 838-845 (1961)

Reflectance and Transmittance of Evaporated Aluminum and Aluminum: Magnesium Fluoride Films in the Ultraviolet (>1800 Å)

B. Bates and D. J. Bradley
J. Opt. Soc. Am. 57(4) 481-485 (1967)

Infrared Reflectance of Evaporated Aluminum Films

H. E. Bennett, Jean M. Bennett, and E. J. Ashley
J. Opt. Soc. Am. 52(11) 1245-1250 (1962)

On the Vacuum-Ultraviolet Reflectance of Evaporated Aluminum before and during Oxidation*

R. P. Madden, L. R. Canfield, and G. Hass
J. Opt. Soc. Am. 53(5) 620-625 (1963)

Anodically Produced Multiple Oxide Films for Increasing the Reflectance of Evaporated Aluminum*

Georg Hass and Alan P. Bradford
J. Opt. Soc. Am. 44(10) 810-815 (1954)