To main content

Charge carrier passivating nitrogen-phosphorus defects in crystalline silicon

Abstract

In this work, the geometric and electronic structure of the neutral and charged nitrogen–phosphorus defects were for the first time rigorously investigated by density functional theory. The ground state structures were located by screening all possible geometric configurations of the defects. It is shown that the modified self-interstitial nitrogen–phosphorus defect passivate the free carrier states of isolated substitutional phosphorus, known to be an excellent dopant in crystalline silicon. Furthermore, the band gap is shown to be similar in magnitude to bulk silicon, but direct. However, this study indicate that the nitrogen–phosphorus defect is possibly less stable than the self-interstitial nitrogen dimer at high nitrogen defect concentrations. Finally, the vibrational spectra were analyzed by means of linear response theory and phonon calculations. The resulting vibrational spectra yield a peak split of the modified self-interstitial nitrogen mode of 4 THz compared to the isolated self-interstitial nitrogen defect.

Category

Academic article

Language

English

Author(s)

Affiliation

  • University of Oslo
  • SINTEF Industry / Sustainable Energy Technology

Year

2015

Published in

Computational Materials Science

ISSN

0927-0256

Publisher

Elsevier

Volume

98

Page(s)

220 - 225

View this publication at Cristin