The growth of transparent amorphous carbon thin films from coal

Large-area, uniform, transparent amorphous carbon (a-C) thin films were synthesized through simple chemical vapor deposition using coal as the solid carbon source. The atomic force microscopy characterization showed that the synthesized carbon thin film has ∼5 nm thickness with ∼0.55 nm surface roughness. The optical transmittance spectrum showed that the carbon thin film has >96% optical transmittance over the spectral range from 350 nm to 900 nm. The carbon thin films can be transferred to various substrates, which show promise for applications in solar cell, optical and magnetic storage disks, light emitting diodes, photodiodes, and biomedical implants.