The origin of infrared bands in nitrogen-doped Si

摘要

This work reports Fourier-transform infrared spectroscopy (FTIR) investigations on electron irradiated, nitrogen-doped Czochralski-grown silicon (Cz-Si). The study focuses mainly on the detection and thermal evolution of bands related to various nitrogen (N) and vacancy-nitrogen substitutional (VN)-related defects formed prior and after the irradiation of the material. Thus, in the first place, we refer to the presence of bands related to N impurity in the range 640-720 cm(-1) of IR spectra, where most VN defects are expected to give signals. tau hen, by following the thermal evolution of the detected IR bands and by considering the formation energies of the various N and VN defects, we discuss their possible correlation with different N or VN defects. We suggest that (i) the 650 cm(-1) band relates to the N-s and with the VN1 at different temperature ranges, (ii) the 655 cm(-1) relates to the N-s defect, (iii) the 660 cm(-1) relates to the VN1 defect, (iv) the 678 cm(-1) band relates to the N-i-N-s defect and the V2N2 defect at different temperature ranges, (v) the 684 cm(-1) band relates to the VN2 defect, and (vi) the 689 cm(-1) band relates to the N-i, VN1 and V2N2 defect at different temperature ranges.