TY - JOUR
T1 - The interstitial carbon–dioxygen center in irradiated silicon
AU - Potsidi, Marianna S.
AU - Kuganathan, Navaratnarajah
AU - Christopoulos, Stavros Richard G.
AU - Chroneos, Alexander
AU - Angeletos, Theoharis
AU - Sarlis, Nicholas V.
AU - Londos, Charalampos A.
N1 - Funding Information:
Acknowledgments: T. Angeletos is grateful to the A. S. Onassis Foundation for financial support through his Ph.D. scholarship (Grant No. G ZL 001-1/2015-2016).
Publisher Copyright:
© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2020/11/1
Y1 - 2020/11/1
N2 - We investigated, experimentally as well as theoretically, defect structures in electron irradiated Czochralski-grown silicon (Cz-Si) containing carbon. Infrared spectroscopy (IR) studies observed a band at 1020 cm−1 arisen in the spectra around 300◦C. Its growth occurs concomitantly with the decay out of the well-known vacancy-oxygen (VO) defect, with a Local Vibrational Mode (LVM) at 830 cm−1 and carbon interstitial-oxygen interstitial (CiOi) defect with a LVM at 862 cm−1, in silicon (Si). The main purpose of this work is to establish the origin of the 1020 cm−1 band. One potential candidate is the carbon interstitial-dioxygen (CiO2i) defect since it is expected to form upon annealing out of the CiOi pair. To this end, systematic density functional theory (DFT) calculations were used to predict the lowest energy structure of the (CiO2i) defect in Si. Thereafter, we employed the dipole–dipole interaction method to calculate the vibrational frequencies of the structure. We found that CiO2i defect has an LVM at ~1006 cm−1, a value very close to our experimental one. The analysis and study of the results lead us to tentatively correlate the 1020 cm−1 band with the CiO2i defect.
AB - We investigated, experimentally as well as theoretically, defect structures in electron irradiated Czochralski-grown silicon (Cz-Si) containing carbon. Infrared spectroscopy (IR) studies observed a band at 1020 cm−1 arisen in the spectra around 300◦C. Its growth occurs concomitantly with the decay out of the well-known vacancy-oxygen (VO) defect, with a Local Vibrational Mode (LVM) at 830 cm−1 and carbon interstitial-oxygen interstitial (CiOi) defect with a LVM at 862 cm−1, in silicon (Si). The main purpose of this work is to establish the origin of the 1020 cm−1 band. One potential candidate is the carbon interstitial-dioxygen (CiO2i) defect since it is expected to form upon annealing out of the CiOi pair. To this end, systematic density functional theory (DFT) calculations were used to predict the lowest energy structure of the (CiO2i) defect in Si. Thereafter, we employed the dipole–dipole interaction method to calculate the vibrational frequencies of the structure. We found that CiO2i defect has an LVM at ~1006 cm−1, a value very close to our experimental one. The analysis and study of the results lead us to tentatively correlate the 1020 cm−1 band with the CiO2i defect.
KW - DFT calculations
KW - IR spectroscopy
KW - Irradiation
KW - Silicon
UR - http://www.scopus.com/inward/record.url?scp=85095763352&partnerID=8YFLogxK
U2 - 10.3390/cryst10111005
DO - 10.3390/cryst10111005
M3 - Article
AN - SCOPUS:85095763352
VL - 10
JO - Crystals
JF - Crystals
SN - 2073-4352
IS - 11
M1 - 1005
ER -