Structure and magnetic properties of Fe epitaxial thin films prepared by UHV rf magnetron sputtering on GaAs single-crystal substrates
Abstract Fe thin films were prepared on GaAs single-crystal substrates of (100) B 3 , (110) B 3 , and (111) B 3 orientations by ultra high vacuum rf magnetron sputtering. The effects of substrate orientation and substrate temperature on the film growth, the structure, and the magnetic properties were investigated. On GaAs(100) B 3 substrates, Fe(100) bcc single-crystal films are obtained at 300 °C, whereas Fe films consisting of bcc(100) and bcc(221) crystals epitaxially grow at room temperature (RT). Fe(110) bcc and Fe(111) bcc single-crystal films are respectively obtained on GaAs(110) B 3 and GaAs(111) B 3 substrates at RT–300 °C. The in-plane lattice spacings of these Fe epitaxial films are 0–9% larger than the out-of-plane lattice spacings due to accommodation of lattice mismatch between the films and the substrates. The film strain is decreased by employing an elevated substrate temperature of 300 °C. The in-plane magnetization properties are reflecting the magnetocrystalline anisotropy of bulk bcc–Fe crystal.