Characteristics of the electromagnetic interference shielding effectiveness of Al-doped ZnO thin films deposited by atomic layer deposition
Autor: | Geun Young Yeom, David W. Johnson, Yong June Choi, Stephen L. Golledge, Hyung Ho Park, Su Cheol Gong |
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Rok vydání: | 2013 |
Předmět: |
Materials science
Dopant Doping Analytical chemistry General Physics and Astronomy Nanotechnology Surfaces and Interfaces General Chemistry Condensed Matter Physics Surfaces Coatings and Films Ion Atomic layer deposition Electrical resistivity and conductivity Transmittance Thin film Deposition (law) |
Zdroj: | Applied Surface Science. 269:92-97 |
ISSN: | 0169-4332 |
Popis: | The structural, optical, and electrical properties of Al-doped ZnO (ZnO:Al) thin films deposited by atomic layer deposition (ALD) with a modified precursor pulse sequence were investigated to evaluate the electromagnetic interference shielding effectiveness (EMI-SE). A Zn–Al–O precursor exposure sequence was used in a modified ALD procedure to result in better distribution of Al3+ ions in the ZnO matrix with the aim of reducing the formation of complete nano-laminated structures that may form in the typical alternating ZnO and Al2O3 deposition procedure. The ALD dopant concentration of the ZnO:Al films was varied by adjusting the dopant deposition intervals of the ZnO:Zn Al O precursor pulse cycle ratios among 24:1, 19:1, 14:1, and 9:1. The lowest obtained resistivity and average transmittance in the visible region (380-780 nm) were 5.876 × 10−4 Ω cm (carrier concentration of 6.02 × 1020 cm−3 and Hall mobility of 17.65 cm2/V s) and 85.93% in the 131 nm thick ZnO:Al(19:1) film, respectively. The average value of the EMI-SE in the range of 30 MHz to 1.5 GHz increased from 1.1 dB for the 121 nm thick undoped ZnO film to 6.5 dB for the 131 nm thick ZnO:Al(19:1) film. |
Databáze: | OpenAIRE |
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