EPR determination of radiation defects in neutron-irradiated silicon

A method was developed of the measurement and evaluation of EPR spectra of radiation defects and it was tested by measuring the defects formed in Si irradiated with reactor neutrons, both at room temperature and after heating the sample to various temperatures up to 480 degC. The absolute method of determining the g factor, corrected for magnetic field variations with distance from the magnet poles, yields g factors with a relative error of ±2x10-4. Samples of n-Si of a specific resistance of 10 ohm.cm were used for the experiments. Irradiation was carried out using the research reactor of the Institute of Nuclear Research, Rez, and all spectra were measured in the sample orientation <100> parallel to H→. The EPR spectra revealed unambiguously the presence of Si-P3 centers (neutral state of tetravacancy, V40) and Si-P1 centers (pentavacancy with one unpaired electron, V5-). (author). 7 figs., 6 tabs., 10 refs