Local Variation of Scattering Light Intensity in Manganese Ion Implanted Silicon Single Crystals

This article presents the results of experimental studies of local changes in the scattered light intensity and surface morphology in Mn implanted single-crystal silicon samples with electron conductivity and [100] crystalline orientation. The manganese ion energy, implantation dose, and phosphorus concentration in substrate were 40 keV, 5⋅1015÷1⋅1017 ion/cm2, and ~ 9,3⋅1014 cm–3, respectively. Atomic force microscopy (AFM) and Raman spectroscopy, using the backscattering geometry of surface-scattered light, were applied to analyze the surface morphology before and after implantation. AFM micrographs of the surface show characteristic nanometer-sized roughnesses, the shape and size of which strongly depend on the implantation dose. These nanoscale objects are not present on the non-implanted substrate surface. In the Raman spectra of the samples not subjected to implantation, the main Lorentz-type peak is always observed, which is characteristic of single-crystal silicon and centered at 520.0±1.0 cm−1, corresponding to the phonon wave vector. Several peaks are observed in the Raman spectra of manganese ion-implanted silicon samples (184, 291, 373, 468, 659, 798, and 804 cm−1), presumably associated with the formation of radiation defects and nanoscale objects on the surface of single-crystal silicon during ion implantation with the participation of silicon, manganese, phosphorus, and other impurity atoms. These structural defects in the silicon crystal lattice at the surface and near-surface caused by manganese ion bombardment lead to the excitation of new vibrational modes not observed in the initial silicon. These modes are manifested in Raman scattering spectra.

Not yet translated