Highly conductive air-stable ZnO thin film formation under in situ UV illumination for an indium-free transparent electrode. Issue 73 (20th July 2016)

• Record Type: Journal Article
• Authors: Cho, Boram; Kim, Hongbum; Yang, Dasom; Shrestha, Nabeen K.; Sung, Myung Mo
• Is Part Of: RSC advances. Volume 6:Issue 73(2016)
• Page Start: 69027
• Page End: 69032
• Publication Date: 2016-07-20
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra13430k
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : In situ UV irradiation during ALD cycles generates oxygen-vacancies, partially removes O–H bonds, and thereby produces a highly transparent and highly conductive air-stable ZnO film. Abstract : Zinc oxide (ZnO) is considered as the strongest alternative to tin doped indium oxide (ITO) – a commonly used, but an expensive state-of-the-art material for transparent conducting electrodes. This work reports the low temperature atomic layer deposition (ALD) of a highly transparent, and highly conductive air-stable thin film of ZnO under in situ UV irradiation of the growing film. X-ray photoelectron spectroscopy (XPS) reveals that the UV irradiation generates oxygen vacancies, partially removes O–H bonds, and thereby improves the electrical conductivity. Thus, in contrast to 0.25 Ω cm resistivity of the pristine ZnO film, the in situ UV irradiated ZnO film shows an electrical resistivity of 5.5 × 10 −4 Ω cm, and an optical transparency of nearly 90%, which are closer to that of ITO. In addition, even on prolonged exposure of the film to air, it demonstrates high stability against the degradation of the electrical conductivity.