This paper reports the controlled growth of atomically sharp In2O3/ZnO and In2O3/Li‐doped ZnO (In2O3/Li‐ZnO) heterojunctions via spin‐coating at 200 °C and assesses their application in n‐channel thin‐film transistors (TFTs). It is shown that addition of Li in ZnO leads to n‐type doping and allows for the accurate tuning of its Fermi energy. In the case of In2O3/ZnO heterojunctions, presence of the n‐doped ZnO layer results in an increased amount of electrons being transferred from its conduction band minimum to that of In2O3over the interface, in a process similar to modulation doping. Electrical characterization reveals the profound impact of the presence of the n‐doped ZnO layer on the charge transport properties of the isotype In2O3/Li‐ZnO heterojunctions as well as on the operating characteristics of the resulting TFTs. By judicious optimization of the In2O3/Li‐ZnO interface microstructure, and Li concentration, significant enhancement in both the electron mobility and TFT bias stability is demonstrated.
- Award ID(s):
- 2011401
- NSF-PAR ID:
- 10411313
- Date Published:
- Journal Name:
- Nanomaterials
- Volume:
- 12
- Issue:
- 3
- ISSN:
- 2079-4991
- Page Range / eLocation ID:
- 565
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/nano12030565
