Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditions
Indium-zinc-oxide (IZO) films were prepared by spin coating an ethanol-ethylene-glycol precursor solution with a Zn/(In + Zn) ratio of 0.36 on glass. The effects of temperature on the structure, microstructure, electrical, and optical properties of the IZO thin films were investigated by thermal ana...
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| Format: | Article |
| Language: | English |
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Elsevier
2023-09-01
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| Series: | Heliyon |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2405844023069529 |
| _version_ | 1827803116713541632 |
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| author | Izabela Stojanoska Miha Okorn Brigita Kmet Hana Uršič Vera Gradišnik Duško Čakara Janez Kovač Danjela Kuscer |
| author_facet | Izabela Stojanoska Miha Okorn Brigita Kmet Hana Uršič Vera Gradišnik Duško Čakara Janez Kovač Danjela Kuscer |
| author_sort | Izabela Stojanoska |
| collection | DOAJ |
| description | Indium-zinc-oxide (IZO) films were prepared by spin coating an ethanol-ethylene-glycol precursor solution with a Zn/(In + Zn) ratio of 0.36 on glass. The effects of temperature on the structure, microstructure, electrical, and optical properties of the IZO thin films were investigated by thermal analysis, Fourier-transform infrared spectroscopy, X-ray diffraction, electron and atomic-force microscopy, X-ray photoelectron spectroscopy and variable-angle spectroscopic ellipsometry. The prepared IZO thin films heated at 500, 600, and 700 °C in air were transparent, without long-range ordering, and with an RMS surface roughness of less than 1 nm. The lowest electrical resistivity at room temperature, 0.0069 Ωcm, was observed for the 115-nm-thick IZO thin film heated at 600 °C in air and subsequently post-annealed in Ar/H2. The thin film exhibited a microstructure characterized by grains typically 20 nm in size and had no organic residues. This film exhibits uniaxial optical anisotropy due to its ultra-thin lamellae with a high electron density. The ordinary refractive index was fitted as a Tauc-Lorentz-Urbach function, which is typical of an indirect absorption edge occurring in amorphous semiconductor materials. The principal absorption peak with an onset at about 2.8 eV and a Tauc gap energy of ∼2.6 eV is similar to those observed for In2O3. The described process of chemical solution deposition and subsequent curing is promising for the low-cost fabrication of IZO thin films for transparent electronics, and can be used to tune the structure and microstructure of IZO thin films, as well as their electrical and optical properties. |
| first_indexed | 2024-03-11T20:49:58Z |
| format | Article |
| id | doaj.art-ced62b8deeca446e86e4408413e8de56 |
| institution | Directory Open Access Journal |
| issn | 2405-8440 |
| language | English |
| last_indexed | 2024-03-11T20:49:58Z |
| publishDate | 2023-09-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Heliyon |
| spelling | doaj.art-ced62b8deeca446e86e4408413e8de562023-10-01T06:01:06ZengElsevierHeliyon2405-84402023-09-0199e19744Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditionsIzabela Stojanoska0Miha Okorn1Brigita Kmet2Hana Uršič3Vera Gradišnik4Duško Čakara5Janez Kovač6Danjela Kuscer7Jožef Stefan Institute, Ljubljana, SloveniaJožef Stefan Institute, Ljubljana, SloveniaJožef Stefan Institute, Ljubljana, SloveniaJožef Stefan Institute, Ljubljana, SloveniaUniversity of Rijeka, Faculty of Engineering, Rijeka, Croatia; Center for Micro- and Nanosciences and Technologies, Rijeka, CroatiaUniversity of Rijeka, Department of Biotechnology, Croatia; Center for Micro- and Nanosciences and Technologies, Rijeka, CroatiaJožef Stefan Institute, Ljubljana, SloveniaJožef Stefan Institute, Ljubljana, Slovenia; Corresponding author.Indium-zinc-oxide (IZO) films were prepared by spin coating an ethanol-ethylene-glycol precursor solution with a Zn/(In + Zn) ratio of 0.36 on glass. The effects of temperature on the structure, microstructure, electrical, and optical properties of the IZO thin films were investigated by thermal analysis, Fourier-transform infrared spectroscopy, X-ray diffraction, electron and atomic-force microscopy, X-ray photoelectron spectroscopy and variable-angle spectroscopic ellipsometry. The prepared IZO thin films heated at 500, 600, and 700 °C in air were transparent, without long-range ordering, and with an RMS surface roughness of less than 1 nm. The lowest electrical resistivity at room temperature, 0.0069 Ωcm, was observed for the 115-nm-thick IZO thin film heated at 600 °C in air and subsequently post-annealed in Ar/H2. The thin film exhibited a microstructure characterized by grains typically 20 nm in size and had no organic residues. This film exhibits uniaxial optical anisotropy due to its ultra-thin lamellae with a high electron density. The ordinary refractive index was fitted as a Tauc-Lorentz-Urbach function, which is typical of an indirect absorption edge occurring in amorphous semiconductor materials. The principal absorption peak with an onset at about 2.8 eV and a Tauc gap energy of ∼2.6 eV is similar to those observed for In2O3. The described process of chemical solution deposition and subsequent curing is promising for the low-cost fabrication of IZO thin films for transparent electronics, and can be used to tune the structure and microstructure of IZO thin films, as well as their electrical and optical properties.http://www.sciencedirect.com/science/article/pii/S2405844023069529Chemical solution depositionIndium zinc oxideThin filmsMicrostructure |
| spellingShingle | Izabela Stojanoska Miha Okorn Brigita Kmet Hana Uršič Vera Gradišnik Duško Čakara Janez Kovač Danjela Kuscer Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditions Heliyon Chemical solution deposition Indium zinc oxide Thin films Microstructure |
| title | Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditions |
| title_full | Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditions |
| title_fullStr | Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditions |
| title_full_unstemmed | Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditions |
| title_short | Indium-zinc-oxide thin films produced by low-cost chemical solution deposition: Tuning the microstructure, optical and electrical properties with the processing conditions |
| title_sort | indium zinc oxide thin films produced by low cost chemical solution deposition tuning the microstructure optical and electrical properties with the processing conditions |
| topic | Chemical solution deposition Indium zinc oxide Thin films Microstructure |
| url | http://www.sciencedirect.com/science/article/pii/S2405844023069529 |
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