X-RAY-DIFFRACTION BEHAVIOR OF W TI SUPERLATTICES/

The structural properties of periodic and quasiperiodic W/Ti superlatt ices have been investigated by means of X-ray diffraction. Intensity a ttenuation of even ordered peaks occurs in the spectra of W/Ti periodi c superlattices with near-equal-layer thicknesses. This phenomenon is theoretically explained. Two series of quasiperiodic (Fibonacci) sampl es are prepared, one with thickness ratio d(A)/d(B) = tau, and the oth er d(A)/d(B) = 1/tau. X-ray diffraction results of these quasiperiodic superlattices are discussed and compared. The possible application of Fibonacci films as optical elements in the soft X-ray region is discu ssed. Furthermore some X-ray diffraction spectra are simulated by comp uter calculation in order to understand the detailed structures. The c alculated results are in good agreement with measured ones.