Enhanced exciton separation through negative energy band bending at grain boundaries of Cu2ZnSnSe4 thin-films

A. R. Jeong; W. Jo; S. Jung; J. Gwak; J. H. Yun

doi:10.1063/1.3626848

Enhanced exciton separation through negative energy band bending at grain boundaries of Cu₂ZnSnSe₄ thin-films

A. R. Jeong, W. Jo, S. Jung, J. Gwak, J. H. Yun

Department of Physics

Research output: Contribution to journal › Article › peer-review

37 Scopus citations

Abstract

Local surface potential of Cu₂ZnSnSe₄ thin-films was investigated by Kelvin probe force microscopy. The surface potential profile across grain boundaries (GBs) shows a rise of 200-600 meV at GBs in a Cu-poor and Zn-poor film with 3.8 efficiency, which means positively charged GBs. In contrast, the GBs in a Cu-poor and Zn-rich film with 2 efficiency exhibit lowering of surface potential by 40 meV. The results indicate that GBs of Cu₂ZnSnSe₄ films play a role for exciton separation and governing defects for high efficiency could be not only Cu_Zn but also V_Cu as explained theoretical predictions.

Original language	English
Article number	082103
Journal	Applied Physics Letters
Volume	99
Issue number	8
DOIs	https://doi.org/10.1063/1.3626848
State	Published - 22 Aug 2011

Bibliographical note

Funding Information:
This research was supported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Knowledge Economy, Republic of Korea (No. 10037233), by KRCF (Korea Research Council of Fundamental Science & Technology), and KIER (Korea Institute of Energy Research) for “NAP (National Agenda Project) program.” This work was supported in part by MEST and DGIST (10-BD-0101, Convergence Technology with New Renewable Energy and Intelligent Robot).

Access to Document

10.1063/1.3626848

Cite this

@article{6a40245950084660b84d8d03211aa8de,

title = "Enhanced exciton separation through negative energy band bending at grain boundaries of Cu2ZnSnSe4 thin-films",

abstract = "Local surface potential of Cu2ZnSnSe4 thin-films was investigated by Kelvin probe force microscopy. The surface potential profile across grain boundaries (GBs) shows a rise of 200-600 meV at GBs in a Cu-poor and Zn-poor film with 3.8 efficiency, which means positively charged GBs. In contrast, the GBs in a Cu-poor and Zn-rich film with 2 efficiency exhibit lowering of surface potential by 40 meV. The results indicate that GBs of Cu2ZnSnSe4 films play a role for exciton separation and governing defects for high efficiency could be not only CuZn but also VCu as explained theoretical predictions.",

author = "Jeong, {A. R.} and W. Jo and S. Jung and J. Gwak and Yun, {J. H.}",

note = "Funding Information: This research was supported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Knowledge Economy, Republic of Korea (No. 10037233), by KRCF (Korea Research Council of Fundamental Science & Technology), and KIER (Korea Institute of Energy Research) for “NAP (National Agenda Project) program.” This work was supported in part by MEST and DGIST (10-BD-0101, Convergence Technology with New Renewable Energy and Intelligent Robot).",

year = "2011",

month = aug,

day = "22",

doi = "10.1063/1.3626848",

language = "English",

volume = "99",

journal = "Applied Physics Letters",

issn = "0003-6951",

publisher = "American Institute of Physics",

number = "8",

}

TY - JOUR

T1 - Enhanced exciton separation through negative energy band bending at grain boundaries of Cu2ZnSnSe4 thin-films

AU - Jeong, A. R.

AU - Jo, W.

AU - Jung, S.

AU - Gwak, J.

AU - Yun, J. H.

N1 - Funding Information: This research was supported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Knowledge Economy, Republic of Korea (No. 10037233), by KRCF (Korea Research Council of Fundamental Science & Technology), and KIER (Korea Institute of Energy Research) for “NAP (National Agenda Project) program.” This work was supported in part by MEST and DGIST (10-BD-0101, Convergence Technology with New Renewable Energy and Intelligent Robot).

PY - 2011/8/22

Y1 - 2011/8/22

N2 - Local surface potential of Cu2ZnSnSe4 thin-films was investigated by Kelvin probe force microscopy. The surface potential profile across grain boundaries (GBs) shows a rise of 200-600 meV at GBs in a Cu-poor and Zn-poor film with 3.8 efficiency, which means positively charged GBs. In contrast, the GBs in a Cu-poor and Zn-rich film with 2 efficiency exhibit lowering of surface potential by 40 meV. The results indicate that GBs of Cu2ZnSnSe4 films play a role for exciton separation and governing defects for high efficiency could be not only CuZn but also VCu as explained theoretical predictions.

AB - Local surface potential of Cu2ZnSnSe4 thin-films was investigated by Kelvin probe force microscopy. The surface potential profile across grain boundaries (GBs) shows a rise of 200-600 meV at GBs in a Cu-poor and Zn-poor film with 3.8 efficiency, which means positively charged GBs. In contrast, the GBs in a Cu-poor and Zn-rich film with 2 efficiency exhibit lowering of surface potential by 40 meV. The results indicate that GBs of Cu2ZnSnSe4 films play a role for exciton separation and governing defects for high efficiency could be not only CuZn but also VCu as explained theoretical predictions.

UR - http://www.scopus.com/inward/record.url?scp=80052398055&partnerID=8YFLogxK

U2 - 10.1063/1.3626848

DO - 10.1063/1.3626848

M3 - Article

AN - SCOPUS:80052398055

SN - 0003-6951

VL - 99

JO - Applied Physics Letters

JF - Applied Physics Letters

IS - 8

M1 - 082103