Formation and Structural Characterization of Cu15Si4 Thin Films on Si(111) by RFMS and DCMS Magnetron Sputtering

Abstract

Copper silicide nanofilms were synthesized via RF and DC magnetron sputtering (MS). RFMS deposition of Cu onto Si(111) at 467°C formed a heteroepitaxial Cu/Cu₁₅Si₄/Si structure, with a 75 nm Cu₁₅Si₄ layer beneath a 130 nm Cu overlayer. DCMS-prepared Cu/Si(111) films were vacuum-annealed at 527°C for 90 minutes, also yielding Cu₁₅Si₄. Film thickness and morphology were characterized by scanning electron microscopy (SEM), and phase formation was confirmed by EDS. The results highlight the influence of Cu crystal size and substrate temperature on silicide formation, demonstrating the potential of copper silicides for enhancing performance in MOS transistors and high-speed integrated circuits.