Reassessment of the intrinsic bulk recombination in crystalline silicon

verfasst von

Tim Niewelt, Bernd Steinhauser, Armin Richter, Boris A. Veith-Wolf, Andreas Fell, B. Hammann, Nicholas Grant, Lachlan Black, J. Tan, A. Youssef, John Murphy, Jan Schmidt, Martin Schubert, Stefan W. Glunz

Abstract

Characterisation and optimization of next-generation silicon solar cell concepts rely on an accurate knowledge of intrinsic charge carrier recombination in crystalline silicon. Reports of measured lifetimes exceeding the previous accepted parameterisation of intrinsic recombination indicate an overestimation of this recombination in certain injection regimes and hence the need for revision. In this work, twelve high-quality silicon sample sets covering a wide doping range are fabricated using state-of-the-art processing routes in order to permit an accurate assessment of intrinsic recombination based on wafer thickness variation. Special care is taken to mitigate extrinsic recombination due to bulk contamination or at the wafer surfaces. The combination of the high-quality samples with refined sample characterisation and lifetime measurements enables a much higher level of accuracy to be achieved compared to previous studies. We observe that reabsorption of luminescence photons inside the sample must be accounted for to achieve a precise description of radiative recombination. With this effect taken into account, we extract the lifetime limitation due to Auger recombination. We find that the extracted Auger recombination rate can accurately be parameterized using a physically motivated equation based on Coulomb-enhanced Auger recombination for all doping and injection conditions relevant for silicon-based photovoltaics. The improved accuracy of data description obtained with the model suggests that our new parameterisation is more consistent with the actual recombination process than previous models. Due to notable changes in Auger recombination predicted for moderate injection, we further revise the fundamental limiting power conversion efficiency for a single-junction crystalline silicon solar cell to 29.4%, which is within 0.1%

_abs compared to other recent assessments.

Externe Organisation(en)

Institut für Solarenergieforschung GmbH (ISFH)
Fraunhofer-Institut für Solare Energiesysteme (ISE)
University of Warwick
Australian National University
SunPower Corporation

Typ

Artikel

Journal

Solar Energy Materials and Solar Cells

Band

235

ISSN

0927-0248

Publikationsdatum

01.2022

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Elektronische, optische und magnetische Materialien, Erneuerbare Energien, Nachhaltigkeit und Umwelt, Oberflächen, Beschichtungen und Folien

Ziele für nachhaltige Entwicklung

SDG 7 – Erschwingliche und saubere Energie

Elektronische Version(en)

https://doi.org/10.1016/j.solmat.2021.111467 (Zugang: Offen)