Far-infrared absorption due to electronic transitions of N–O complexes in Czochralski-grown silicon crystals: Influence of nitrogen and oxygen concentration

Fourier-transform infrared absorption measurements have been carried out on nitrogen-doped Czochralski-grown silicon crystals after thermal annealing at 600°C. The strength of the electronic transitions due to N–O related shallow donors shows a square root dependence on the nitrogen concentration and donor-specific power dependences on the interstitial oxygen concentration. Based on mass action laws, chemical compositions are discussed. It is found that the N–O complexes investigated all involve one nitrogen atom but three different numbers of oxygen atoms.