title: Low-Temperature Atomic Layer Deposition of CuSbS2for Thin-Film Photovoltaics.
abstract: Copper antimony sulfide (CuSbS2) has been gaining traction as an earth-abundant absorber for thin-film photovoltaics given its near ideal band gap for solar energy conversion (∼1.5 eV), large absorption coefficient (>104cm-1), and elemental abundance. Through careful in situ analysis of the deposition conditions, a low-temperature route to CuSbS2thin films via atomic layer deposition has been developed. After a short (15 min) postprocess anneal at 225 °C, the ALD-grown CuSbS2films were crystalline with micron-sized grains, exhibited a band gap of 1.6 eV and an absorption coefficient >104cm-1, as well as a hole concentration of 1015cm-3. Finally, the ALD-grown CuSbS2films were paired with ALD-grown TiO2to form a photovoltaic device. This photovoltaic device architecture represents one of a very limited number of Cd-free CuSbS2PV device stacks reported to date, and it is the first to demonstrate an open-circuit voltage on par with CuSbS2/CdS heterojunction PV devices. While far from optimized, this work demonstrates the potential for ALD-grown CuSbS2thin films in environmentally benign photovoltaics.
authors.affiliation: Department of Chemistry, University of Wisconsin-Stevens Point , Stevens Point, Wisconsin 54481, United States.
authors.forename: Shannon C
authors.identifier: http://orcid.org/0000-0002-7716-6645
authors.initials: SC
authors.lastname: Riha
authors.affiliation: Department of Chemistry, University of Wisconsin-Stevens Point , Stevens Point, Wisconsin 54481, United States.
authors.forename: Alexandra A
authors.initials: AA
authors.lastname: Koegel
authors.affiliation: Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States.|Argonne-Northwestern Solar Energy Research (ANSER) Center, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Jonathan D
authors.identifier: http://orcid.org/0000-0003-4443-441X
authors.initials: JD
authors.lastname: Emery
authors.affiliation: Materials Science Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.|Argonne-Northwestern Solar Energy Research (ANSER) Center, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Pellin
authors.affiliation: Materials Science Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.|Argonne-Northwestern Solar Energy Research (ANSER) Center, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: Alex B F
authors.identifier: http://orcid.org/0000-0003-3916-1672
authors.initials: AB
authors.lastname: Martinson
keywords: CuSbS2; atomic layer deposition; copper antimony sulfide; photovoltaics; ternary metal sulfide; thin film; thin-film solar cell