Effects of deposition termination on Cu2ZnSnSe4 device characteristics

• Published in: Thin solid films Vol. 582; no. C; pp. 184 - 187
• Main Authors: Repins, I.L., Li, J.V., Kanevce, A., Perkins, C.L., Steirer, K.X., Pankow, J., Teeter, G., Kuciauskas, D., Beall, C., Dehart, C., Carapella, J., Bob, B., Park, J.-S., Wei, S.-H.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-05-2015; Elsevier
• Subjects: Constants; Copper zinc tin selenide; Copper zinc tin sulfide; Deposition; Devices; Electric potential; Extrapolation; Flux; Hole barrier; Kesterite; MATERIALS SCIENCE; Solar cell; SOLAR ENERGY; Surface; Thin films; Voltage; Thin films; Solar cell; Hole barrier; Kesterite; Copper zinc tin selenide; Voltage; Copper zinc tin sulfide; Surface
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2014.09.028

Co-evaporated Cu2ZnSnSe4 (CZTSe) is used to examine sensitivities to the device performance that originate from variations in Zn content very near the surface. While integral Zn content of the film is held approximately constant, the surface composition is manipulated via changes to the Zn flux at the end of the deposition. Surface composition, device performance, and open-circuit voltage extrapolated to zero temperature are measured as a function of deposition termination. Origins of the apparent reduction in surface recombination with increasing Zn are discussed.
•Voltage in Cu2ZnSnSe4 solar cells depends on the Zn content at the absorber surface.•Voltage is shown to correlate with measured hole barrier in these devices.•ZnSe does not act as a blocking barrier when it contains several percent Sn and Cu.