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Diamond-like carbon films were prepared by use of a hollow cathode discharge plasma source (HCD), operating at 13.56 MHz. At a distance of 6 cm from the plasma source, a water-cooled substrate holder was positioned, which was biased at 13.56 MHz as well. A plasma-enhanced chemical vapor deposition (PECVD) process was used. Helium as a carrier gas and methane as a source of carbon were used for diamond-like carbon (DLC) film deposition. DLC films were characterized with a micro Raman spectroscopy and spectroscopic ellipsometry. In the wavelength range of 300–900 nm the measured spectra were analyzed by a regression-fitting algorithm, according to the nominal sample structure in which the optical properties of DLC were described by a Cauchy dispersion model. Optimum film quality was obtained in a bias voltage range, between −(350–420) V, which produces the films with the highest index of refraction, close to 2.15; a wavelength of 550 nm; lowest optical band gap close to 1.3 eV; and a Vickers hardness of 30 GPa. It was found that, even in the stationary deposition, mode film thickness variations across a 5-inch wafer did not exceed ±3.5%. A maximum deposition rate of 70–80 nm/min at room temperature was achieved.

Some crucial limiting process steps of ITO/(n)a-Si:H/(p)c-Si solar cell manufacturing were investigated. The influence of amorphous silicon deposition temperature on the efficiency of heterojunction (HJ) solar cells as well as ITO deposition on the properties of ITO/a-Si:H/c-Si interfaces were studied. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and SIMS measurements were employed for the investigations. It was observed that the decrease in a-Si:H deposition temperature from 230 down to 100°C leads to a reduction in solar cell efficiencies to only 1%. It was found that the ITO deposition process itself can significantly modify the ITO/a-Si:H/c-Si interfaces due to the interaction of oxygen, and In and Sn atoms with silicon at the initial stage. It was concluded that this modification has a more significant impact on the quality of the HJ solar cells than on that of the a-Si:H layer.

The properties of the thermosetting polymer mr-I-9000, developed and used for nanoimprint lithography (NIL), were investigated by means of X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The spectra of mr-I-9000 were compared with those of PMMA and show the presence of aromatic rings and a high amount of carbon–carbon and carbon–hydrogen bonds. As a consequence, the mask selectivity of mr-I-9000 in an oxygen and tetrafluoromethane reactive ion etching processes is higher than that for PMMA and slightly different for the cross-linked and non-cross-linked state.