DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Metastability and reliability of CdTe solar cells

Abstract

Thin-film modules of all technologies often suffer from performance degradation over time. Some of the performance changes are reversible and some are not, which makes deployment, testing, and energy-yield prediction more challenging. Manufacturers devote significant empirical efforts to study these phenomena and to improve semiconductor device stability. Still, understanding the underlying reasons of these instabilities remains clouded due to the lack of ability to characterize materials at atomistic levels and the lack of interpretation from the most fundamental material science. The most commonly alleged causes of metastability in CdTe devices, such as ‘migration of Cu’, have been investigated rigorously over the past fifteen years. Still, the discussion often ended prematurely with stating observed correlations between stress conditions and changes in atomic profiles of impurities or CV doping concentration. Multiple hypotheses suggesting degradation of CdTe solar cell devices due to interaction and evolution of point defects and complexes were proposed, and none of them received strong theoretical or experimental confirmation. We believe it should be noted that atomic impurity profiles in CdTe provide very little intelligence on active doping concentrations. The same elements could form different energy states, which could be either donors or acceptors, depending on their position in crystallinemore » lattice. Defects interact with other extrinsic and intrinsic defects; for example, changing the state of an impurity from an interstitial donor to a substitutional acceptor often is accompanied by generation of a compensating intrinsic interstitial donor defect. Moreover, all defects, intrinsic and extrinsic, interact with the electrical potential and free carriers so that charged defects may drift in the electric field and the local electrical potential affects the formation energy of the point defects. Such complexity of interactions in CdTe makes understanding of temporal changes in device performance even more challenging and a closed solution that can treat the entire system and its interactions is required.« less

Authors:
 [1];  [2];  [1];  [1]; ORCiD logo [1]
  1. Arizona State Univ., Tempe, AZ (United States)
  2. San Jose State Univ., CA (United States)
Publication Date:
Research Org.:
Arizona State Univ., Tempe, AZ (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
OSTI Identifier:
1592012
Grant/Contract Number:  
EE0007536; EE0006344
Resource Type:
Accepted Manuscript
Journal Name:
Journal of Physics. D, Applied Physics
Additional Journal Information:
Journal Volume: 51; Journal Issue: 15; Journal ID: ISSN 0022-3727
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; CdTe solar cells; Cu migration; diffusion–reaction modeling

Citation Formats

Guo, Da, Brinkman, Daniel, Shaik, Abdul R., Ringhofer, Christian, and Vasileska, Dragica. Metastability and reliability of CdTe solar cells. United States: N. p., 2018. Web. doi:10.1088/1361-6463/aab1e1.
Guo, Da, Brinkman, Daniel, Shaik, Abdul R., Ringhofer, Christian, & Vasileska, Dragica. Metastability and reliability of CdTe solar cells. United States. https://doi.org/10.1088/1361-6463/aab1e1
Guo, Da, Brinkman, Daniel, Shaik, Abdul R., Ringhofer, Christian, and Vasileska, Dragica. Thu . "Metastability and reliability of CdTe solar cells". United States. https://doi.org/10.1088/1361-6463/aab1e1. https://www.osti.gov/servlets/purl/1592012.
@article{osti_1592012,
title = {Metastability and reliability of CdTe solar cells},
author = {Guo, Da and Brinkman, Daniel and Shaik, Abdul R. and Ringhofer, Christian and Vasileska, Dragica},
abstractNote = {Thin-film modules of all technologies often suffer from performance degradation over time. Some of the performance changes are reversible and some are not, which makes deployment, testing, and energy-yield prediction more challenging. Manufacturers devote significant empirical efforts to study these phenomena and to improve semiconductor device stability. Still, understanding the underlying reasons of these instabilities remains clouded due to the lack of ability to characterize materials at atomistic levels and the lack of interpretation from the most fundamental material science. The most commonly alleged causes of metastability in CdTe devices, such as ‘migration of Cu’, have been investigated rigorously over the past fifteen years. Still, the discussion often ended prematurely with stating observed correlations between stress conditions and changes in atomic profiles of impurities or CV doping concentration. Multiple hypotheses suggesting degradation of CdTe solar cell devices due to interaction and evolution of point defects and complexes were proposed, and none of them received strong theoretical or experimental confirmation. We believe it should be noted that atomic impurity profiles in CdTe provide very little intelligence on active doping concentrations. The same elements could form different energy states, which could be either donors or acceptors, depending on their position in crystalline lattice. Defects interact with other extrinsic and intrinsic defects; for example, changing the state of an impurity from an interstitial donor to a substitutional acceptor often is accompanied by generation of a compensating intrinsic interstitial donor defect. Moreover, all defects, intrinsic and extrinsic, interact with the electrical potential and free carriers so that charged defects may drift in the electric field and the local electrical potential affects the formation energy of the point defects. Such complexity of interactions in CdTe makes understanding of temporal changes in device performance even more challenging and a closed solution that can treat the entire system and its interactions is required.},
doi = {10.1088/1361-6463/aab1e1},
journal = {Journal of Physics. D, Applied Physics},
number = 15,
volume = 51,
place = {United States},
year = {Thu Mar 22 00:00:00 EDT 2018},
month = {Thu Mar 22 00:00:00 EDT 2018}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 16 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Index Reduction and Discontinuity Handling Using Substitute Equations
journal, June 2001

  • F�bi�n, G.; Van Beek, D. A.; Rooda, J. E.
  • Mathematical and Computer Modelling of Dynamical Systems, Vol. 7, Issue 2
  • DOI: 10.1076/mcmd.7.2.173.3646

Numerical modeling of CdS/CdTe and CdS/CdTe/ZnTe solar cells as a function of CdTe thickness
journal, August 2007

  • Amin, Nowshad; Sopian, Kamaruzzaman; Konagai, Makoto
  • Solar Energy Materials and Solar Cells, Vol. 91, Issue 13
  • DOI: 10.1016/j.solmat.2007.04.006

The effect of copper on the sub-bandgap density of states of CdTe solar cells
journal, May 2015

  • Warren, Charles W.; Li, Jiaojiao; Wolden, Colin A.
  • Applied Physics Letters, Vol. 106, Issue 20
  • DOI: 10.1063/1.4921577

Semiconducting Cadmium Telluride
journal, December 1954

  • Jenny, Dietrich A.; Bube, Richard H.
  • Physical Review, Vol. 96, Issue 5, p. 1190-1191
  • DOI: 10.1103/PhysRev.96.1190

Numerical Simulation of Copper Migration in Single Crystal CdTe
journal, September 2016


Chemical trends of defect formation and doping limit in II-VI semiconductors: The case of CdTe
journal, October 2002


Grain-Boundary-Enhanced Carrier Collection in CdTe Solar Cells
journal, April 2014


CdTe solar cells and photovoltaic heterojunctions in II–VI compounds
journal, May 1963


Large-signal analysis of a silicon Read diode oscillator
journal, January 1969

  • Scharfetter, D. L.; Gummel, H. K.
  • IEEE Transactions on Electron Devices, Vol. 16, Issue 1
  • DOI: 10.1109/T-ED.1969.16566

Measurement of Chlorine Concentrations at CdTe Grain Boundaries
journal, November 2014


On the Construction and Comparison of Difference Schemes
journal, September 1968

  • Strang, Gilbert
  • SIAM Journal on Numerical Analysis, Vol. 5, Issue 3
  • DOI: 10.1137/0705041

Controlled activation of ZnTe:Cu contacted CdTe solar cells using rapid thermal processing
journal, February 2015


Solving Ordinary Differential Equations II
book, September 1996


First-principles multiple-barrier diffusion theory: The case study of interstitial diffusion in CdTe
journal, February 2015


Self-consistent simulation of CdTe solar cells with active defects
journal, July 2015

  • Brinkman, Daniel; Guo, Da; Akis, Richard
  • Journal of Applied Physics, Vol. 118, Issue 3
  • DOI: 10.1063/1.4927155

The segregation of copper at high angle grain boundaries in lead
journal, January 1970


CdTe Solar Cells at the Threshold to 20% Efficiency
journal, October 2013


Works referencing / citing this record:

Self-compensation in chlorine-doped CdTe
journal, June 2019

  • Orellana, Walter; Menéndez-Proupin, Eduardo; Flores, Mauricio A.
  • Scientific Reports, Vol. 9, Issue 1
  • DOI: 10.1038/s41598-019-45625-x

Thin‐film solar cells exceeding 22% solar cell efficiency: An overview on CdTe-, Cu(In,Ga)Se 2 -, and perovskite-based materials
journal, December 2018

  • Powalla, Michael; Paetel, Stefan; Ahlswede, Erik
  • Applied Physics Reviews, Vol. 5, Issue 4
  • DOI: 10.1063/1.5061809

Study on the Stability of Unpackaged CdS/CdTe Solar Cells with Different Structures
journal, December 2019

  • Zeng, Guanggen; Liu, Xiaolan; Zhao, Yubo
  • International Journal of Photoenergy, Vol. 2019
  • DOI: 10.1155/2019/3579587

Self-compensation in chlorine-doped CdTe
journal, June 2019

  • Orellana, Walter; Menéndez-Proupin, Eduardo; Flores, Mauricio A.
  • Scientific Reports, Vol. 9, Issue 1
  • DOI: 10.1038/s41598-019-45625-x

Beyond 30% Conversion Efficiency in Silicon Solar Cells: A Numerical Demonstration
journal, August 2019