Journal article
Optimization of annealing for WZ-phase removal and densification in Sb-doped CdSexTe1-x solar cells
Solar energy materials and solar cells, v 306, 114507
15 Oct 2026
Featured in Collection : Drexel's Newest Publications
Abstract
The impact of high temperature annealing (HTA) treatments on the performance of Sb-doped CdSeTe solar cells containing a CdSe0.25Te0.75/CdTe front stack and a vapor transport (VT) deposited CdTe:Sb absorber was studied. The HTA treatment of the thermally evaporated CdSe0.25Te0.75/CdTe front stack converts the mixed-phase film into a single zinc blende structure through recrystallization of the photo-inactive wurtzite phase. Subsequently, HTA treatment of the full device stack after vapor transport deposition of CdTe:Sb absorber promotes Se–Te intermixing, reduces voids, densifies the full stack and enhances CdTe:Sb grain growth. Comprehensive characterizations revealed that the combined HTA treatments significantly improved film crystallinity, removed the WZ phase in the front stack, enhanced full-stack densification, reduced defect densities, and enhanced carrier dynamics. With HTA treatments, the open-circuit voltage (VOC) of CdSeTe:Sb devices increased from ∼400 mV to ≥ 600 mV, and when combined with optimized CdCl2 treatment, VOC reached 849 mV. The net carrier concentrations (NA-ND) of representative devices were NA-ND = 1.5 × 1015, 1.1 × 1015, and 3.5 × 1014 cm-3 for the no-HTA, moderate-HTA, and optimized high-VOC conditions, respectively. Since the highest VOC corresponds to the lowest apparent NA-ND, , which is similar to a Cu-doped-only CdSeTe solar cell (NA-ND≈ 2 × 1014 cm-3), the data indicate that improved device performance does not result from increased electrically active Sb; instead, it points to structural improvement as the dominant effect of HTA. The findings demonstrate the potential of HTA treatments to improve the structural and electrical properties of CdSeXTe1-X solar cells.
•Dual high-temperature anneals (HTA) removes photo-inactive WZ phase.•HTA converts mixed-phase CdSeTe to large-grain zinc blende.•HTA promotes Se–Te intermixing and reduces voids in bi-layer absorbers.•Combined HTA and CdCl2 boost carrier lifetime and suppress non-radiative defects.•Optimized processing achieves cell open-circuit voltage (Voc) up to 849 mV.
Metrics
1 Record Views
Details
- Title
- Optimization of annealing for WZ-phase removal and densification in Sb-doped CdSexTe1-x solar cells
- Creators
- Bin Du (Corresponding Author) - University of DelawareHarvey L. Guthrey - National Laboratory of the RockiesGregory A. Manoukian - Drexel UniversityAntónio J.N. Oliveira - International Iberian Nanotechnology LaboratoryKevin D. Dobson - University of DelawareBrian E. McCandless - University of DelawareJason B. Baxter - Drexel UniversityWilliam N. Shafarman - University of Delaware
- Publication Details
- Solar energy materials and solar cells, v 306, 114507
- Publisher
- Elsevier
- Number of pages
- 10
- Grant note
- U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE) under the Solar Energy Technologies Office: DE-EE0009344 National Renewable Energy Laboratory, United States U.S. Department of Energy (DOE): DE-AC36-08GO28308 U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Solar Energy Technologies Office FCT FSE: 2020.04564.BD
This material is based upon work supported by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE) under the Solar Energy Technologies Office Award Number DE-EE0009344. This work was authored by the National Renewable Energy Laboratory, United States, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding provided by U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Solar Energy Technologies Office. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes. A. J. N. Oliveira acknowledges FCT and FSE under grant 2020.04564.BD.
- Resource Type
- Journal article
- Language
- English
- Academic Unit
- Chemical and Biological Engineering
- Web of Science ID
- WOS:001806706500001
- Other Identifier
- 991022193896604721