Epitaxial Au(111) thin films are grown in controlled high vacuum deposition systems using a magnetron sputtering technique. Details on the deposition technique can be found here. The gold source target is made of pure gold 99.99%. The films are grown at high temperature in a controlled argon atmosphere.
Epitaxial growth of thin films refers to extended single-crystal film formation on top of a crystalline substrate. The structural crystalline quality of the films is checked by X-ray-diffraction analysis. The next figure shows an example of a θ-2θ X-ray analysis performed on a typical 70nm thick gold film.
The analysis shows a pure (111) growth with a c-axis lattice parameter of 2.36 Å. Moreover, the finite number of diffracting planes leads to oscillations of diffracted intensities whose period is related to the layer thickness. The occurrence of these oscillations around the (111) reflection indicates a high degree of crystallinity of the samples and allows us to precisely control the thickness of the films.