Accession Number : ADP008025

Title :   Interfacial Roughness and Interdiffusion Derived from a Comparison of the Measured and Calculated Reflectances of Mo/Si Multilayer Coatings,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s) : Seely, J.F. ; Kowalski, M.P. ; Barbee, T.W. ; Rife, J.C. ; Hunter, W.R.

Report Date : 05 MAR 1992

Pagination or Media Count : 4

Abstract : Mo/Si multilayer coatings were fabricated at LLNL and were characterized using the Grating/Crystal Monochromator and Reflectometer attached to the Naval Research Laboratory beamline X24C at the National Synchrotron Light Source. The reflectances were measured at several angles of incidence and for both s and p polarizations. The measured reflectances were compared to calculations that included the effects of interdiffusion layers and of roughness at each interface and that were based on Henke's optical constants. The dispersive element was a 2400 groove/mm gold-coated grating operated on blaze, and the resolving power of the monochromator was 600. The reflectometer was rotated by 90 deg. about the incident radiation beam to measure reflectances in both polarization orientations. An aluminum, silicon, or boron filter was used to attenuate higher order radiation. Shown in Fig. 1 is the measured polarization of the light emerging from the exit slit of the monochromator, (I sub h - I sub v)/(I sub h + I sub v), at the time when the data was taken. I sub h refers to the intensity of light with the electric vector in the horizontal plane, and I sub v refers to the intensity with the electric vector in the vertical plane.

Descriptors :   *POLARIZATION, *REFLECTANCE, ALUMINUM, BEAMS(RADIATION), BORON, COATINGS, CRYSTALS, GOLD, INTENSITY, INTERFACES, LABORATORIES, LAYERS, LIGHT SOURCES, MONOCHROMATORS, NAVAL RESEARCH LABORATORIES, RADIATION, REFLECTOMETERS, ROUGHNESS, SILICON, SYNCHROTRONS, LOW ANGLES.

Subject Categories : Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE