Evolution of local work function in epitaxial VO 2 thin films spanning the metal-insulator transition

Ahrum Sohn; Haeri Kim; Dong Wook Kim; Changhyun Ko; Shriram Ramanathan; Jonghyurk Park; Giwan Seo; Bong Jun Kim; Jun Hwan Shin; Hyun Tak Kim

doi:10.1063/1.4766292

Evolution of local work function in epitaxial VO ₂ thin films spanning the metal-insulator transition

Ahrum Sohn, Haeri Kim, Dong Wook Kim, Changhyun Ko, Shriram Ramanathan, Jonghyurk Park, Giwan Seo, Bong Jun Kim, Jun Hwan Shin, Hyun Tak Kim

Department of Physics

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

33 Scopus citations

Abstract

Transport and Kelvin probe force microscopy measurements were simultaneously conducted on epitaxial VO ₂ thin films. The samples work function abruptly dropped from 4.88 eV to 4.70 eV during heating from 333 K to 353 K, suggesting a significant change in its electronic band structure spanning the metal insulator transition. The work function showed nearly no statistical deviation across the films surface during the transition, likely due to band bending at the boundaries of the small domains. Resistance profiles confirmed that the local work function corresponded closely to the resistance of the corresponding area.

Original language	English
Article number	191605
Journal	Applied Physics Letters
Volume	101
Issue number	19
DOIs	https://doi.org/10.1063/1.4766292
State	Published - 5 Nov 2012

Bibliographical note

Funding Information:
This work was supported by the Quantum Metamaterials Research Center (2009-0063324), the Basic Research Program (2010-0009344), through the National Research Foundation of Korea Grant funded by the Korean Ministry of Education, Science, and Technology (MEST), and a Korea-CIS project of MEST in Korea, and MIT Creative Research Project in ETRI. C.K. and S.R. acknowledge AFOSR Grant No. FA9550-08-1-0203 for financial support.

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10.1063/1.4766292

Cite this

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title = "Evolution of local work function in epitaxial VO 2 thin films spanning the metal-insulator transition",

abstract = "Transport and Kelvin probe force microscopy measurements were simultaneously conducted on epitaxial VO 2 thin films. The samples work function abruptly dropped from 4.88 eV to 4.70 eV during heating from 333 K to 353 K, suggesting a significant change in its electronic band structure spanning the metal insulator transition. The work function showed nearly no statistical deviation across the films surface during the transition, likely due to band bending at the boundaries of the small domains. Resistance profiles confirmed that the local work function corresponded closely to the resistance of the corresponding area.",

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note = "Funding Information: This work was supported by the Quantum Metamaterials Research Center (2009-0063324), the Basic Research Program (2010-0009344), through the National Research Foundation of Korea Grant funded by the Korean Ministry of Education, Science, and Technology (MEST), and a Korea-CIS project of MEST in Korea, and MIT Creative Research Project in ETRI. C.K. and S.R. acknowledge AFOSR Grant No. FA9550-08-1-0203 for financial support.",

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AU - Ko, Changhyun

AU - Ramanathan, Shriram

AU - Park, Jonghyurk

AU - Seo, Giwan

AU - Kim, Bong Jun

AU - Shin, Jun Hwan

AU - Kim, Hyun Tak

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PY - 2012/11/5

Y1 - 2012/11/5

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