Atomic diffusion in annealed Cu/SiO₂/Si (100) system prepared by magnetron sputtering

Cu thin films are deposited on p-type Si (100) substrates by magnetron sputtering at room temperature. The interface reaction and atomic diffusion of Cu/SiO₂/Si (100) systems are studied by x-ray diffraction (XRD) and Rutherford backscattering spectrometry (RBS). Some significant results can be obtained. The onset temperature of interdiffusion for Cu/SiO₂/Si(100) is 350 ℃. With the annealing temperature increasing, the interdiffusion becomes more apparent. The calculated diffusion activation energy is about 0.91 eV. For the Cu/SiO₂/Si (100) systems copper silicides are not formed below an annealing temperature of 350 ℃. The formation of the copper silicides phase is observed when the annealing temperature arrives at 450 ℃.