The behavior of fcc Cu nanocrystallites in Si(100)

Cu has been implanted in Si(100) at room temperature with a dose of 1.67 and 6.43 × 10¹⁶ ions cm^-2. HRTEM observations show the Cu cluster size in as-implanted state is increased as the amount of implanted Cu ion doses increased from 3.65 nm for 1.67 × 10¹⁶ ions cm^-2 to 5.24 nm for 6.43 × 10¹⁶ ions cm^-2. Using diffraction patterns from several orientations and using a lattice parameter for Si a_Si = 0.543 nm, the lattice parameter for the fee Cu cluster is found to be a_Cu = 0.353 nm. X-ray absorption spectroscopy performed at the K-edge of Cu on as-implanted samples and on samples annealed at 1073 K for 4 h showed that Cu precipitated in the Si(100) matrix. The interatomic distances (0.255 nm) in the nearest neighbor atoms (Cu-Cu) for all samples did not change.