TY - JOUR

T1 - Reassessment of the intrinsic bulk recombination in crystalline silicon

AU - Niewelt, Tim

AU - Steinhauser, Bernd

AU - Richter, Armin

AU - Veith-Wolf, Boris A.

AU - Fell, Andreas

AU - Hammann, B.

AU - Grant, Nicholas

AU - Black, Lachlan

AU - Tan, J.

AU - Youssef, A.

AU - Murphy, John

AU - Schmidt, Jan

AU - Schubert, Martin

AU - Glunz, Stefan W.

N1 - Funding information: This work was funded by the German Federal Ministry for Economic Affairs and Energy ( BMWi ) in project LIMES under the contract numbers 0324204 A ( University of Freiburg ), 0324204C ( Fraunhofer ISE) and 0324204D ( ISFH ). Work at the University of Warwick was supported by the Engineering and Physical Sciences Research Council ( EP/M024911/1 ) and the Leverhulme Trust ( RPG-2020-377 ). Work at the Australian National University was supported by the Australian Renewable Energy Agency ( ARENA ) through project RND017.

PY - 2022/1

Y1 - 2022/1

N2 - 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.

AB - 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.

KW - Auger recombination

KW - Charge carrier lifetime

KW - Intrinsic recombination

KW - Parameterisation

KW - Silicon

KW - Single-junction maximum efficiency

UR - http://www.scopus.com/inward/record.url?scp=85119620507&partnerID=8YFLogxK

U2 - 10.1016/j.solmat.2021.111467

DO - 10.1016/j.solmat.2021.111467

M3 - Article

VL - 235

JO - Solar Energy Materials and Solar Cells

JF - Solar Energy Materials and Solar Cells

SN - 0927-0248

M1 - 111467

ER -