Acceptor-oxygen defects in silicon: The electronic properties of centers formed by boron, gallium, indium, and aluminum interactions with the oxygen dimer

Abstract

Paper published as part of the special topic on Defects in Semiconductors 2022 This paper was selected as an Editor's Pick ARTICLES YOU MAY BE INTERESTED IN Impact of thermal annealing on deep levels in nitrogen-implanted β-Ga 2 O 3 Schottky barrier diodes

Spectroscopic Investigation of Shallow Hole Traps in Ga- and B-doped Czochralski Silicon: Insight into Light-Induced Degradation

“…An increase in acceptor size also results in weaker binding energies for complexes involving Ga acceptor atoms. 15 We observe that the fine structure of the Ga-doped Cz Si does not change upon 1 Sun illumination, and the sample remains paramagnetic after 24 hr of exposure. The energy levels for the B and Ga acceptors are 0.045 and 0.065 eV, respectively.…”

“…We observe a sharp EPR signal at ∼330 mT, which is due to background contamination within the EPR sample cavity. An increase in acceptor size also results in weaker binding energies for complexes involving Ga acceptor atoms . We observe that the fine structure of the Ga-doped Cz Si does not change upon 1 Sun illumination, and the sample remains paramagnetic after 24 hr of exposure.…”

“…A recent study has revealed that a very similar substitutional acceptor atom−dioxygen complex is expected to form in Ga-doped Cz Si, and the electronic properties of this defect should be similar to those of the B−O defect. 15 To date, most of the studies on detecting LID in Ga-doped Cz Si 16 rely on quasi-steady-state photoconductance decay (QSSPCD) 17,18 measurements, which rely on assumptions about the capture cross section ratio and defect energy levels in the fitting of the lifetime curves. 19 With the Si photovoltaic market rapidly transitioning to Ga-doped PERC solar cells to avoid performance degradation due to LID, it is of great interest to understand the differences between B-and Ga-doped Cz Si at the atomic level.…”

“…This signal is associated with the deep donor state of the complex made of a substitutional acceptor atom (B a or Ga a ) and the oxygen dimer. 15,30 Subsequently, conventional DLTS measurements over the temperature range 295−425 K were conducted on diodes fabricated with B-and Ga-doped Cz Si, which were subjected to LID conditions for 20 and 70 hr. The aim of these treatments was to convert the B−O defect state from the annealed state to the degraded state.…”

“…Regardless of the extent of LID in Ga-doped Cz Si, the reason why B-doped Cz Si undergoes LID and Ga-doped Cz Si is more stable remains unclear. A recent study has revealed that a very similar substitutional acceptor atom–dioxygen complex is expected to form in Ga-doped Cz Si, and the electronic properties of this defect should be similar to those of the B–O defect . To date, most of the studies on detecting LID in Ga-doped Cz Si rely on quasi-steady-state photoconductance decay (QSSPCD) , measurements, which rely on assumptions about the capture cross section ratio and defect energy levels in the fitting of the lifetime curves .…”