Next Article in Journal
Effect of Boron on Hot Ductility and Room-Temperature Tensile Properties of Microalloyed Steels with Titanium and Niobium
Previous Article in Journal
Fractal Analysis of the Fracture Evolution of Freeze-Thaw Damage to Asphalt Concrete
Previous Article in Special Issue
Emission Enhancement of Cu-Doped InP Quantum Dots through Double Shelling Scheme
Open AccessArticle

Band to Band Tunneling at the Zinc Oxide (ZnO) and Lead Selenide (PbSe) Quantum Dot Contact; Interfacial Charge Transfer at a ZnO/PbSe/ZnO Probe Device

Department of Materials Science and Engineering, Hongik University 72-1, Sangsu-dong, Mapo-gu, Seoul 04066, Korea
*
Authors to whom correspondence should be addressed.
Materials 2019, 12(14), 2289; https://doi.org/10.3390/ma12142289
Received: 25 June 2019 / Revised: 11 July 2019 / Accepted: 15 July 2019 / Published: 17 July 2019
(This article belongs to the Special Issue Quantum Dots and Applications)
We provide a comprehensive understanding of interfacial charge transfer at the lead selenide (PbSe) quantum dot (QD)/zinc oxide (ZnO) interface, proposing band to band tunneling process as a charge transfer mechanism in which initial hopping of carriers from ZnO to PbSe QDs is independent of temperature. Using the transmission line method (TLM) in a ZnO/PbSe/ZnO geometry device, we measured the ZnO/PbSe electrical contact resistance, a measure of charge transfer efficiency. Fabrication of a highly conductive ZnO film through Al doping allows for the formation of ZnO source and drain electrodes, replacing conventional metal electrodes. We found that band to band tunneling at the PbSe QD/ZnO interface governs charge transfer based on temperature-independent PbSe QD/ZnO contact resistance. In contrast, the PbSe QD channel sheet resistance decreased as the temperature increased, indicating thermally activated transport process in the PbSe QD film. These results demonstrate that, at the ZnO/PbSe QD interface, temperature-independent tunneling process initiates carrier injection followed by thermally activated carrier hopping, determining the electrical contact resistance. View Full-Text
Keywords: ZnO; PbSe; quantum dot; field effect transistor; localized states; charge transfer ZnO; PbSe; quantum dot; field effect transistor; localized states; charge transfer
Show Figures

Figure 1

MDPI and ACS Style

Kim, M.; Han, C.-Y.; Yang, H.; Park, B. Band to Band Tunneling at the Zinc Oxide (ZnO) and Lead Selenide (PbSe) Quantum Dot Contact; Interfacial Charge Transfer at a ZnO/PbSe/ZnO Probe Device. Materials 2019, 12, 2289.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop