Doping efficiency and plasma analysis of a nitrogen electron cyclotron resonance plasma

Abstract

The active nitrogen species of an electron cyclotron resonance plasma source used for doping of II–VI films is investigated. Experiments include plasma analysis by mass spectroscopy and optical emission spectroscopy and doping experiments. The nitrogen content in ZnTe:N layers grown by molecular beam epitaxy quantifies the doping efficiency of the source. The plasma operating parameters dependence of the N content is compared to the mass spectroscopy and plasma induced emission signals of atoms, molecules and ions. The observed atom flux of about 1015 cm−2 s−1 at the source exit plane can account for the measured doping level, if contribution from only N atoms is considered. However, the observed discrepancy between the pressure dependence of the atom concentration and the doping level would suggest a contribution from a molecular species.