Charakterisierung dünner mit dem Laser-Arc abgeschiedener DLC-Schichten mit UV-VIS und IR-Spektroskopie

The new deposition method with laser-induced controlled vacuum arc (Laser-Arc) was used for the thin film deposition of diamond-like carbon films on different materials (KBr, KCl, NaCl, ZnSe, KRS-5, Ge, c-Si and Corning 7059). The substrates were cleaned by argon sputtering for 10 minutes at 200 Cel. Carbon films with a thickness between 50 nm and 200 nm deposited at different deposition rates (0.1-1 nm/s) and pulse durations (37 microseconds, 100 microseconds) are studied. A special moveable substrate holder was used to deposit an all-face protective DLC-coating onto the surfaces of the salt substrates and an one-sided coating onto ZnSe-, KRS-5, Ge and Corning substrates. The coated substrates are characterized by UV / VIS / NIR and an FTIR spectroscopy in the wavenumber range between 400 cm (exp -1) and 50,000 cm (exp -1). Transmission and reflection measurements of the films on Corning 7059 were used to determine the absorption index and the Tauc-gap, that correlates with the deposi tion conditions and the hydrogen content, respectively. In the infrared spectra of the double sided coatings transmittances above 90% have been observed. However between 1,000 cm (exp -1) and 1,300 cm (exp -1) the coatings show antireflectance properties. The content of bonded hydrogen was determined by detailed investigations of the absorption curves.