Deposition of thin films of copper on silicon substrates at low temperature by the ICB method

Abstract

Deposition by the ICB method of pure aluminum and gold epitaxial films on silicon substrates raised the question whether this technique may improve the characteristics of other metal films on silicon. Results of ICB deposition of Cu on Si(111) near room temperature in ultrahigh vacuum (UHV) are reported herein. The growing film was analyzed in situ by the RMEED and XPS techniques. In addition, the final films (900 Å thick) were analyzed by RHEED and X-ray diffraction. The measurements suggest epitaxial growth, at least in the early stages of film formation and the presence of different crystalline orientations in the final films which have a smooth surface with no silicon segregation. In contrast to previously reported results on aluminium and gold films, no appreciable differences were detected between films deposited with neutral beams and with accelerated (3 kV) ionized beams.