Semiconducting amorphous carbon thin films for transparent conducting electrodes

Semiconducting amorphous carbon thin films were directly grown on SiO2 substrate by using chemical vapor deposition. Raman spectra and transmission electron microscopy image showed that the a-C films have a short-range ordered amorphous structure. The electrical and optical properties of the a-C thin films were investigated. The films have sheet resistance of 3.7kΩ/□ and high transmittance of 82%. They exhibit metal-oxide-semiconductor field effect transistor mobility of 10–12cm2V−1s−1 at room temperature, which is comparable to previous reported mobility of amorphous carbon. The optical band gap was calculated by Tauc’s relationship and photoluminescence spectra showed that the films are semiconductor with an optical band gap of 1.8eV. These good physical properties make the a-C films a candidate for the application of transparent conducting electrodes.