Fabrication of Transparent and Conductive SWCNT/SiO₂ Composite Thin-Film by Photo-Irradiation of Molecular Precursor Films

Abstract

A single-walled carbon nanotube (SWCNT)-silica composite thin film on a quartz glass was formed by ultraviolet irradiation (20–40 °C) onto a spin-coated precursor film. With 7.4 mass% SWCNTs, the electrical resistivity reached 7.7 × 10−3 Ω·cm after UV-irradiation. The transmittance was >80% at 178–2600 nm, and 79%–73% at 220–352 nm. Heat treatment increased the transparency and pencil hardness, without affecting the low electrical resistivity. Raman spectroscopy and microscopic analyses revealed the excellent film morphology with good SWCNT dispersal. The low refractive index (1.49) and haze value (<1.5%) are invaluable for transparent windows for novel optoelectronic devices.

Keywords

• deep ultraviolet
• vacuum ultraviolet
• near infrared
• transparent
• conductive thin film
• SWCNT/SiO₂