Realistic efficiency potential of next-generation industrial Czochralski-grown silicon solar cells after deactivation of the boron-oxygen-related defect center

verfasst von
Dominic C. Walter, Bianca Lim, Jan Schmidt
Abstract

We measure carrier lifetimes of different Czochralski-grown silicon (Cz-Si) materials of various boron and oxygen concentrations and determine the maximum achievable lifetime after an optimized thermal treatment. We obtain very high and stable bulk lifetimes of several milliseconds, virtually eliminating the boron–oxygen (BO) defect complex, which previously limited the carrier lifetime in boron-doped Cz-Si materials after prolonged illumination. Based on these experimental results, we introduce a new parameterization of the bulk lifetime of B-doped Cz-Si after permanent deactivation of the BO center. Notably, we measure lifetimes up to 4 ms on 2-Ωcm Cz-Si wafers at an injection level of 1/10 of the doping concentration. Importantly, these high lifetime values can be reached within 10 and 20 s of BO deactivation treatment. A detailed analysis of the injection-dependent lifetimes reveals that the lifetimes after permanent deactivation of the BO center can be well described by a single-level recombination center characterized by an electron-to-hole capture cross-section ratio of 12 and located in the middle of the silicon band gap. We implement the novel parameterization into a two-dimensional device simulation of a passivated emitter and rear solar cell using technologically realistic cell parameters. The simulation reveals that based on current state-of-the-art solar cell production technology, efficiencies reaching 22.1% are realistically achievable in the near future after complete deactivation of the BO center.

Organisationseinheit(en)
Institut für Festkörperphysik
Externe Organisation(en)
Institut für Solarenergieforschung GmbH (ISFH)
Typ
Artikel
Journal
Progress in Photovoltaics: Research and Applications
Band
24
Seiten
920-928
Anzahl der Seiten
9
ISSN
1062-7995
Publikationsdatum
17.06.2016
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Elektronische, optische und magnetische Materialien, Erneuerbare Energien, Nachhaltigkeit und Umwelt, Physik der kondensierten Materie, Elektrotechnik und Elektronik
Ziele für nachhaltige Entwicklung
SDG 7 – Erschwingliche und saubere Energie
Elektronische Version(en)
https://doi.org/10.1002/pip.2731 (Zugang: Geschlossen)