Enhanced p-Type Doping in Polycrystalline CdTe Films: Deposition and Activation
Abstract
An in situ nonequilibrium method to increase hole density in polycrystalline CdTe thin films to 1016 cm-3 using group V substitution on Te is presented. Single-phase CdTe films doped with P, As, and Sb were deposited at 550 degrees C at 100-200 nm/s onto moving cadmium sulfide/high resistance transparent buffer layer/transparent conductive oxide /glass superstrates by vapor transport deposition in Cd overpressure from high purity compound sources. Doping levels before and after activation were determined by capacitance-voltage analysis of diagnostic devices. Secondary ion mass spectrometry depth profiling confirmed dopant incorporation levels of 1017 -1018 atoms/cm3 in as-deposited films. Electronic activation was carried out by post-deposition annealing in Cd or CdCl2 vapor with fast cooling, increasing acceptor concentrations to >1015 cm-3 for P and >1016 cm-3 for As and Sb, compared with mid -1014 cm-3 acceptor levels for undoped CdTe films. The activation methods are compatible with post-deposition processing presently used for high-efficiency CdTe solar cells. For the dopants As and Sb, the acceptor concentration increased by substitutional As Te and Sb Te formation, respectively, which was validated by cathodoluminescence spectroscopy.
- Authors:
-
- Univ. of Delaware, Newark, DE (United States)
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Publication Date:
- Research Org.:
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- OSTI Identifier:
- 1514851
- Report Number(s):
- NREL/JA-5K00-73937
Journal ID: ISSN 2156-3381
- Grant/Contract Number:
- AC36-08GO28308
- Resource Type:
- Accepted Manuscript
- Journal Name:
- IEEE Journal of Photovoltaics
- Additional Journal Information:
- Journal Volume: 9; Journal Issue: 3; Journal ID: ISSN 2156-3381
- Publisher:
- IEEE
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 14 SOLAR ENERGY; 36 MATERIALS SCIENCE; CdTe; doping; photovoltaic; thin film
Citation Formats
McCandless, Brian, Buchanan, Wayne, Sriramagiri, Gowri, Thompson, Christopher, Duenow, Joel N., Albin, David S., Jensen, Soeren A., Moseley, John, Al-Jassim, Mowafak M., and Metzger, Wyatt K. Enhanced p-Type Doping in Polycrystalline CdTe Films: Deposition and Activation. United States: N. p., 2019.
Web. doi:10.1109/JPHOTOV.2019.2902356.
McCandless, Brian, Buchanan, Wayne, Sriramagiri, Gowri, Thompson, Christopher, Duenow, Joel N., Albin, David S., Jensen, Soeren A., Moseley, John, Al-Jassim, Mowafak M., & Metzger, Wyatt K. Enhanced p-Type Doping in Polycrystalline CdTe Films: Deposition and Activation. United States. https://doi.org/10.1109/JPHOTOV.2019.2902356
McCandless, Brian, Buchanan, Wayne, Sriramagiri, Gowri, Thompson, Christopher, Duenow, Joel N., Albin, David S., Jensen, Soeren A., Moseley, John, Al-Jassim, Mowafak M., and Metzger, Wyatt K. Wed .
"Enhanced p-Type Doping in Polycrystalline CdTe Films: Deposition and Activation". United States. https://doi.org/10.1109/JPHOTOV.2019.2902356. https://www.osti.gov/servlets/purl/1514851.
@article{osti_1514851,
title = {Enhanced p-Type Doping in Polycrystalline CdTe Films: Deposition and Activation},
author = {McCandless, Brian and Buchanan, Wayne and Sriramagiri, Gowri and Thompson, Christopher and Duenow, Joel N. and Albin, David S. and Jensen, Soeren A. and Moseley, John and Al-Jassim, Mowafak M. and Metzger, Wyatt K.},
abstractNote = {An in situ nonequilibrium method to increase hole density in polycrystalline CdTe thin films to 1016 cm-3 using group V substitution on Te is presented. Single-phase CdTe films doped with P, As, and Sb were deposited at 550 degrees C at 100-200 nm/s onto moving cadmium sulfide/high resistance transparent buffer layer/transparent conductive oxide /glass superstrates by vapor transport deposition in Cd overpressure from high purity compound sources. Doping levels before and after activation were determined by capacitance-voltage analysis of diagnostic devices. Secondary ion mass spectrometry depth profiling confirmed dopant incorporation levels of 1017 -1018 atoms/cm3 in as-deposited films. Electronic activation was carried out by post-deposition annealing in Cd or CdCl2 vapor with fast cooling, increasing acceptor concentrations to >1015 cm-3 for P and >1016 cm-3 for As and Sb, compared with mid -1014 cm-3 acceptor levels for undoped CdTe films. The activation methods are compatible with post-deposition processing presently used for high-efficiency CdTe solar cells. For the dopants As and Sb, the acceptor concentration increased by substitutional As Te and Sb Te formation, respectively, which was validated by cathodoluminescence spectroscopy.},
doi = {10.1109/JPHOTOV.2019.2902356},
journal = {IEEE Journal of Photovoltaics},
number = 3,
volume = 9,
place = {United States},
year = {Wed Mar 20 00:00:00 EDT 2019},
month = {Wed Mar 20 00:00:00 EDT 2019}
}
Web of Science