In the journal "Journal of Materials Science and Engineering", Volume 37, Issue 1, 2019,“HNHT” published a paper titled "Effects of preparation process parameters on the structure and optical properties of hydrogen-free diamond-like carbon films", which belongs to the National Natural Science Foundation funded project (51562008), the National Key Research and Development Program funded project (2016YFC0700804), and the Hainan Provincial Key Research and Development Program funded project (ZDYF2016017).

Hydrogen free DLC thin films were prepared on glass substrates and monocrystalline silicon wafers by radio frequency magnetron sputtering. The structure and optical properties of DLC thin films prepared under different process parameters were characterized by various technical means.

The results show that changes in sputtering power, operating pressure, substrate temperature, and argon flow rate have significant effects on the structure, transmittance, and optical band gap of the thin film. The internal sp3 bond content, visible light transmittance, and optical band gap of the thin film decrease with increasing sputtering power or substrate temperature, increase with increasing operating pressure, and first increase and then decrease with increasing argon flow rate. DLC thin films with an ID/IG of 0.86, an average transmittance of 85% in the visible region, and an optical band gap of 1.68 eV can be prepared at a working pressure of 2.0 Pa.