Effect of annealing treatment on transparent and conductive hydrated magnesium-carbon films

• Published in: Journal of alloys and compounds 2019-03, Vol.778, p.83-89
• Main Authors: Guo, Shuai, Yang, Lei, Dai, Bing, Geng, Fangjuan, Yang, Zhenhuai, Lei, Pei, Wang, Peng, Gao, Gang, Han, Jiecai, Ralchenko, Victor, Zhu, Jiaqi
• Format: Article
• Language: English
• Subjects: Annealing; Carbon; Conductivity; Electrical properties; Electronic materials; Energy gap; Far infrared radiation; Hydrated magnesium-carbon films; Infrared spectra; Light transmittance; Magnesium hydroxide; Magnetron sputtering; Optical properties; Optoelectronic devices; Thin films; Transparent conductive films
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2018.11.027

Transparent electronic technology has many urgent optoelectronic device applications. A key component of plasmonic materials in conventional semiconductors is the wide band gap of oxide thin films. Although transparent electronic materials have been developed for visible and near-infrared wavelengths, systems incorporating mid-infrared and far-infrared spectra are difficult to achieve. In this study, hydrated magnesium-carbon films, a new type of non-oxide transparent conductive thin films with a magnesium hydroxide structure, were generated using the three-step method. After annealing treatment, larger crystals in the thin films typically exhibited superior film resistivity, with conductivity values of approximately 8.63 × 10−3 Ω m. Due to the free electron concentration was not more than 1020 cm−3, the films demonstrated excellent optical properties, with plasma wavelength values of approximately 8 μm for infrared transmittance above 70%. After annealing, due to the Moss-Burstein (M-B) effect, the visible light transmittance was greater than 85% and the optical bandgap shifted towards the blue region. In addition, the influences of the sputtering power of the carbon target on the properties of hydrated magnesium-carbon film were also discussed in this paper. [Display omitted] •We prepare hydrated magnesium-carbon films using the three-step method.•We analyze the effect of annealing on structural, electrical, and optical features.•Annealing leads to crystal growth, superior film resistivity, and good conductivity.•Films exhibit excellent optical properties, particularly for far-infrared ranges.•The films can replace TCO in the application of optical-electronic devices.