Band offset at the heterojunction interfaces of CdS/ZnSnP{sub 2}, ZnS/ZnSnP{sub 2}, and In{sub 2}S{sub 3}/ZnSnP{sub 2}

Journal Article · Sat May 21 00:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4950882· OSTI ID:22596699

Nakatsuka, Shigeru; Nose, Yoshitaro; Shirai, Yasuharu ^[1]

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1. Department of Materials Science and Engineering, Kyoto University, Kyoto 606-8501 (Japan)

Heterojunctions were formed between ZnSnP{sub 2} and buffer materials, CdS, ZnS, and In{sub 2}S{sub 3}, using chemical bath deposition. The band offset was investigated by X-ray photoelectron spectroscopy based on Kraut method. The conduction band offset, ΔE{sub C}, between ZnSnP{sub 2} and CdS was estimated to be −1.2 eV, which significantly limits the open circuit voltage, V{sub OC}. Conversely, ΔE{sub C} at the heterojunction between ZnSnP{sub 2} and ZnS was +0.3 eV, which is within the optimal offset range. In the case of In{sub 2}S{sub 3}, ΔE{sub C} was a relatively small value, −0.2 eV, and In{sub 2}S{sub 3} is potentially useful as a buffer layer in ZnSnP{sub 2} solar cells. The J−V characteristics of heterojunction diodes with an Al/sulfides/ZnSnP{sub 2} bulk/Mo structure also suggested that ZnS and In{sub 2}S{sub 3} are promising candidates for buffer layers in ZnSnP{sub 2} thin film solar cells, and the band alignment is a key factor for the higher efficiency of solar cells with heterojunctions.

• OSTI ID: 22596699
• Journal Information: Journal of Applied Physics, Vol. 119, Issue 19; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALIGNMENT
BUFFERS
CADMIUM SULFIDES
ELECTRIC POTENTIAL
HETEROJUNCTIONS
INDIUM SULFIDES
LAYERS
SOLAR CELLS
THIN FILMS
TIN PHOSPHATES
X-RAY PHOTOELECTRON SPECTROSCOPY
ZINC PHOSPHATES
ZINC SULFIDES