ELECTRON-PARAMAGNETIC-RESONANCE VERSUS SPIN-DEPENDENT RECOMBINATION -EXCITED TRIPLET-STATES OF STRUCTURAL DEFECTS IN IRRADIATED SILICON

Upon illumination some structural defects in irradiated silicon can be excited into the metastable triplet S=1 states. These triplet states can be involved in the excess-carriers recombination process. This pap er provides a theoretical treatment of spin-dependent recombination (S DR) via an excited triplet state and reports on the properties of its electron-paramagnetic-resonance (EPR) spectrum detected by means of de and microwave photoconductivity changes under magnetic-resonance cond itions. The dependence of the spectral lines intensity on various expe rimental parameters (microwave power and phase, size of the sample) ha s been investigated and a comparison between the two techniques and th e conventional EPR method has been made. Using the SDR technique the a ngular dependence of the Line positions and intensities for the struct ural defects in their excited triplet states was studied and the spin- Hamiltonian parameters of the Si-PT1 and Si-PT4 spectra have been dete rmined.