Optical and thermal ionization of iron-related defects in silicon

The optical and thermal ionization energies of several Fe-related defects in Fe-diffused Si are determined simultaneously using the photostimulated capacitance transient method together with deep-level transient spectroscopy. Two defect states with thermal electron-ionization energies of 0.36 and 0.56 eV to the conduction band, respectively, are confirmed to originate from the Fe-related defects, in addition to the donor level due to interstitial Fe. The origins of these defects are discussed on the basis of their behaviors in n- and p-type Si. (author)