skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Long carrier lifetimes in large-grain polycrystalline CdTe without CdCl{sub 2}

Abstract

For decades, polycrystalline CdTe thin films for solar applications have been restricted to grain sizes of microns or less whereas other semiconductors such as silicon and perovskites have produced devices with grains ranging from less than a micron to more than 1 mm. Because the lifetimes in as-deposited polycrystalline CdTe films are typically limited to less than a few hundred picoseconds, a CdCl{sub 2} treatment is generally used to improve the lifetime; but this treatment may limit the achievable hole density by compensation. Here, we establish methods to produce CdTe films with grain sizes ranging from hundreds of nanometers to several hundred microns by close-spaced sublimation at industrial manufacturing growth rates. Two-photon excitation photoluminescence spectroscopy shows a positive correlation of lifetime with grain size. Large-grain, as-deposited CdTe exhibits lifetimes exceeding 10 ns without Cl, S, O, or Cu. This uncompensated material allows dopants such as P to achieve a hole density of 10{sup 16 }cm{sup −3}, which is an order of magnitude higher than standard CdCl{sub 2}-treated devices, without compromising the lifetime.

Authors:
; ; ; ; ; ; ;
Publication Date:
OSTI Identifier:
22590667
Resource Type:
Journal Article
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 108; Journal Issue: 26; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0003-6951
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CADMIUM CHLORIDES; CADMIUM TELLURIDES; CARRIER LIFETIME; DOPED MATERIALS; EXCITATION; GRAIN SIZE; HOLES; PEROVSKITES; PHOTOLUMINESCENCE; POLYCRYSTALS; SEMICONDUCTOR MATERIALS; SPECTROSCOPY; SUBLIMATION; THIN FILMS

Citation Formats

Jensen, S. A., E-mail: Soren.Jensen@nrel.gov, E-mail: Wyatt.Metzger@nrel.gov, Burst, J. M., Duenow, J. N., Guthrey, H. L., Moseley, J., Moutinho, H. R., Johnston, S. W., Kanevce, A., Al-Jassim, M. M., and Metzger, W. K., E-mail: Soren.Jensen@nrel.gov, E-mail: Wyatt.Metzger@nrel.gov. Long carrier lifetimes in large-grain polycrystalline CdTe without CdCl{sub 2}. United States: N. p., 2016. Web. doi:10.1063/1.4954904.
Jensen, S. A., E-mail: Soren.Jensen@nrel.gov, E-mail: Wyatt.Metzger@nrel.gov, Burst, J. M., Duenow, J. N., Guthrey, H. L., Moseley, J., Moutinho, H. R., Johnston, S. W., Kanevce, A., Al-Jassim, M. M., & Metzger, W. K., E-mail: Soren.Jensen@nrel.gov, E-mail: Wyatt.Metzger@nrel.gov. Long carrier lifetimes in large-grain polycrystalline CdTe without CdCl{sub 2}. United States. https://doi.org/10.1063/1.4954904
Jensen, S. A., E-mail: Soren.Jensen@nrel.gov, E-mail: Wyatt.Metzger@nrel.gov, Burst, J. M., Duenow, J. N., Guthrey, H. L., Moseley, J., Moutinho, H. R., Johnston, S. W., Kanevce, A., Al-Jassim, M. M., and Metzger, W. K., E-mail: Soren.Jensen@nrel.gov, E-mail: Wyatt.Metzger@nrel.gov. Mon . "Long carrier lifetimes in large-grain polycrystalline CdTe without CdCl{sub 2}". United States. https://doi.org/10.1063/1.4954904.
@article{osti_22590667,
title = {Long carrier lifetimes in large-grain polycrystalline CdTe without CdCl{sub 2}},
author = {Jensen, S. A., E-mail: Soren.Jensen@nrel.gov, E-mail: Wyatt.Metzger@nrel.gov and Burst, J. M. and Duenow, J. N. and Guthrey, H. L. and Moseley, J. and Moutinho, H. R. and Johnston, S. W. and Kanevce, A. and Al-Jassim, M. M. and Metzger, W. K., E-mail: Soren.Jensen@nrel.gov, E-mail: Wyatt.Metzger@nrel.gov},
abstractNote = {For decades, polycrystalline CdTe thin films for solar applications have been restricted to grain sizes of microns or less whereas other semiconductors such as silicon and perovskites have produced devices with grains ranging from less than a micron to more than 1 mm. Because the lifetimes in as-deposited polycrystalline CdTe films are typically limited to less than a few hundred picoseconds, a CdCl{sub 2} treatment is generally used to improve the lifetime; but this treatment may limit the achievable hole density by compensation. Here, we establish methods to produce CdTe films with grain sizes ranging from hundreds of nanometers to several hundred microns by close-spaced sublimation at industrial manufacturing growth rates. Two-photon excitation photoluminescence spectroscopy shows a positive correlation of lifetime with grain size. Large-grain, as-deposited CdTe exhibits lifetimes exceeding 10 ns without Cl, S, O, or Cu. This uncompensated material allows dopants such as P to achieve a hole density of 10{sup 16 }cm{sup −3}, which is an order of magnitude higher than standard CdCl{sub 2}-treated devices, without compromising the lifetime.},
doi = {10.1063/1.4954904},
url = {https://www.osti.gov/biblio/22590667}, journal = {Applied Physics Letters},
issn = {0003-6951},
number = 26,
volume = 108,
place = {United States},
year = {2016},
month = {6}
}

Works referencing / citing this record:

Obtaining Large Columnar CdTe Grains and Long Lifetime on Nanocrystalline CdSe, MgZnO, or CdS Layers
journal, January 2018


Grain boundary passivation by CdCl2 treatment in CdTe solar cells revealed by Kelvin probe force microscopy
journal, October 2018


Point defect engineering in thin-film solar cells
journal, June 2018


Overcoming Carrier Concentration Limits in Polycrystalline CdTe Thin Films with In Situ Doping
journal, September 2018


Defect interactions and the role of complexes in the CdTe solar cell absorber
journal, January 2017


Carrier density and lifetime for different dopants in single-crystal and polycrystalline CdTe
journal, November 2016


The roles of carrier concentration and interface, bulk, and grain-boundary recombination for 25% efficient CdTe solar cells
journal, June 2017


Luminescence methodology to determine grain-boundary, grain-interior, and surface recombination in thin-film solar cells
journal, September 2018