?
Models of deep centres in gallium phosphide
The effects of varying the ammonia flux on the concentrations of background Si and free carriers and on deep traps for majority and minority carriers in n-GaP layers grown by vapour epitaxy have been studied by secondary ion mass spectrometry and deep level transient spectroscopy. The contribution from the background silicon to the free carrier concentration in samples variously doped with nitrogen is discussed. It is shown that the deep centre at Ec - 0.24 eV may be attributed to silicon. The model of this centre, in the form SiGa-Vp accounts for experimental results obtained in the present work and those already reported. The concentration of the dominant nonradiative recombination centre at EV + 0.75 eV is studied, depending on growth conditions, and its model is proposed in the form of a complex consisting of intrinsic defects.The effects of varying the ammonia flux on the concentrations of background Si and free carriers and on deep traps for majority and minority carriers in n-GaP layers grown by vapour epitaxy have been studied by secondary ion mass spectrometry and deep level transient spectroscopy. The contribution from the background silicon to the free carrier concentration in samples variously doped with nitrogen is discussed. It is shown that the deep centre at Ec - 0.24 eV may be attributed to silicon. The model of this centre, in the form SiGa-Vp accounts for experimental results obtained in the present work and those already reported. The concentration of the dominant nonradiative recombination centre at EV + 0.75 eV is studied, depending on growth conditions, and its model is proposed in the form of a complex consisting of intrinsic defects.