EPR characteristics of radiation-induced defects in Ge-rich α-quartz

• Published in: Solid state sciences 2022-03, Vol.125, p.106833, Article 106833
• Main Authors: Mashkovtsev, Rudolf I., Balitsky, Vladimir S., Pan, Yuanming
• Format: Article
• Language: English
• Subjects: EPR; Germanium; Quartz; Radiation-induced centers
• ISSN: 1293-2558; 1873-3085
• DOI: 10.1016/j.solidstatesciences.2022.106833

Electron paramagnetic resonance (EPR) in a synthetic Si0.975Ge0.025O2 single crystal of α–quartz structure has been studied. After fast electron irradiation previously studied and new Ge-related paramagnetic centers (PCs) have been recognized using computer simulation of the observed EPR spectra. Increasing radiation doses allow to distinguish four paramagnetic [GeO4/M+]0 centers AGeLi, CGeLi, DGeLi, and AGeNa as well as four oxygen-vacancy electron centers Ge Eˊ1, Ge Eˊ2, Ge(IV) and a new Ge(V) center. The selective UV bleaching and distinct thermal stability of different centers allow us to determine the spin Hamiltonian parameters for the Ge(V) center. Electron paramagnetic resonance (EPR) in a synthetic Si0.975Ge0.025O2 single crystal of α–quartz structure has been studied. Detailed EPR measurements after different storage times, radiation doses, thermal annealing, and UV bleaching as well as computer simulations allow us to distinguish four [GeO4/M+]0 centers AGeLi, CGeLi, DGeLi, and AGeNa as well as four oxygen-vacancy electron centers Ge Eˊ1, Ge Eˊ2, Ge(IV) and Ge(V). The spin Hamiltonian parameters (g, A(73Ge) and P(73Ge) of the new Ge(V) center have been determined and are closely comparable to those of the Ge Eˊ1 center. [Display omitted] •Single crystals of Ge-rich α-quartz were grown hydrothermally.•Ge-related paramagnetic defects are induced by fast electron irradiation.•Paramagnetic defects are identified using computer simulations of EPR spectra.•Spin Hamiltonian parameters for new Ge(V) oxygen vacancy defect are determined.