Carrier Lifetime as a Function of Se Content for CdSexTe1-x Films Grown on Al2O3 and MgZnO

Conference · Thu Aug 26 04:00:00 EDT 2021

DOI:https://doi.org/10.1109/PVSC43889.2021.9518914· OSTI ID:1823785

McGott, Deborah L.; Good, Brian; Fluegel, Brian; Duenow, Joel N.; Wolden, Colin A.; Reese, Matthew O.

Time-resolved photoluminescence (TRPL) with two excitation wavelengths – 670 (standard) and 405 nm – was used to examine the effect on carrier lifetime of two significant recent advances in CdTe: the incorporation of Se to form graded CdSe x Te 1-x and the use of Mg y Zn 1-y O buffers. The two excitation wavelengths probe depths of approximately 130 and 35 nm, respectively, and their comparison helps differentiate interface and bulk contributions to carrier lifetime. It was found that x = 0.2 Se was required to obtain lifetime improvements, primarily in the bulk. Additionally, TRPL traces for Mg y Zn 1-y O/CdSe x Te 1-x samples showed fast initial decay followed by a long-lived tail, which may be indicative of trap-dominated recombination. This behavior was not present for CdSe x Te 1-x films grown on Al 2 O 3 , which is currently state-of-the-art for surface passivation in CdTe. This indicates that further work is required to sufficiently passivate the front interface.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: U.S. Department of Defense (DOD), Office of Naval Research; USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
• DOE Contract Number: AC36-08GO28308; AC36-08GO28308
• OSTI ID: 1823785
• Report Number(s): NREL/CP-5K00-81139; MainId:79915; UUID:c074d97c-af7b-4f6d-8955-e5b56ec2323a; MainAdminID:63097
• Country of Publication: United States
• Language: English

Related Subjects

CdSeTe
MZO
SOLAR ENERGY
TRPL
cadmium telluride
front interface