X-Ray Reflection Studies of the Anneal and Oxidation of Some Thin Solid Films

Abstract

The technique of the total reflection of x rays has been applied to the study of thin films of Cu, Ni, Ge, and Se vacuum-deposited onto polished glass substrates. Starting with fresh films, ``smooth'' enough to exhibit pronounced x-ray interference fringes in the region just beyond the critical angle, the effects of vacuum anneal and oxidation were studied. Changes in the reflection curves are interpreted in terms of possible structural changes in the films. Reflection from layers of particles of carbon or polystyrene latex deposited onto ``smooth'' substrates was also studied for comparison.

The non-specular scattering of X-rays from thin films

“…It has been shown by many workers (Kiessig, 1931;Wainfan & Parratt, 1960;Parratt, 1954) that X-rays incident upon the surface of a material at small glancing angles are specularly reflected, the reflection coefficient being in excellent agreement with the re-* Supported by National Aeronautics and Space Administration grant t The work reported here is taken, in part, from a dissertation presented to the faculty of the Polytechnic Institute of Brooklyn in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Physics), 1969, flectivity predicted by the Fresnel equations (Born & Wolf, 1964). Since the index of refraction for most materials is less than unity at X-ray frequencies, the X-ray beam will be totally reflected if the angle of incidence (as measured from the surface) is less than a 'critical angle' 0c, and if absorption is negligible.…”

X-ray reflectivity and diffraction investigation on TiN/SiNx nanolayered coatings deposited by magnetron sputtering

“…The modulation period can be determined by the position of the main Bragg peak (Yin et al , 1993):where λ represents the X-ray wavelength, θ m is the Bragg angle corresponding to the m th order reflection, and δ is the average refractive index per layer. The interface width can be estimated by Λ /4( n max +1) (Wainfan and Paratt, 1960), where Λ is the modulation period and n max is the highest order of the observed low angle peaks. Figure 2 shows the effect of substrate bias on modulation period Λ and interface width.…”

Structures, mechanical properties and thermal stability of TiN/SiNx multilayer coatings deposited by magnetron sputtering

“…Only one layer-interference fringe could be observed from the coating with a modulation period of 2.51 nm, and the number of interference fringes increases with an increase in modulation period. The interfacial width between TiN and SiN x layer, which is used to assess the interfacial quality and can be estimated by /4(n max + 1) [17], as a function of modulation period , is shown in Fig. 2, where n max is the highest order of the observed layer-interference fringes.…”