Vacuum-evaporated films of chromium with the A-15 structure

Abstract
Continuous thin films of Cr 200–400 Å thick and predominantly consisting of the A-15 phase were grown by evaporation in high vacuum onto KCl and NaCl substrates held at 300 °C. The films have a chemical purity of better than 98%, determined by 4He Rutherford scattering. The A-15 phase is not stabilized by impurities. The lattice parameter determined by electron diffraction is 4.60 Å. The grain size is about 500 Å. The films did not show superconductivity down to 0.5 °K.