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As previous studies indicated, diamond-like carbon (DLC) layers exhibit outstanding biocompatible properties. Additionally, due to high hardness and high transmittance in infrared and visible parts of spectra it is possible to utilize for application ophthalmic optics. DLC layers are suitable for coating of spectacle lenses, contact lenses and even intraocular lenses. In this paper, we focused on transmittance and wear resistance of different commercially available spectacle lenses with surface modification and lenses with DLC layer. The lens transmittance depends on base material and its surface modification. Commercially manufactured lenses exhibit usual transmittance of 90±5%, while transmittance of DLC coated lenses was lower by 15%. Wear resistance is strongly dependent on surface modification. The results of DLC layers were similar or better than commercially manufactured lenses with surface modification.

Eu3+-doped oxide thin films possess a great potential for several emerging applications in optics, optoelectronics, and sensors. The applications demand maximizing Eu3+ photoluminescence response. Eu-doped ZnO, TiO2, and Lu2O3 thin films were deposited by Pulsed Laser Deposition (PLD). Pulsed UV Laser Annealing (PLA) was utilized to modify the properties of the films. In situ monitoring of the evolution of optical properties (photoluminescence and transmittance) at PLA was realized to optimize efficiently PLA conditions. The changes in optical properties were related to structural, microstructural, and surface properties characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). The substantial increase of Eu3+ emission was observed for all annealed materials. PLA induces crystallization of TiO2 and Lu2O3 amorphous matrix, while in the case of already nanocrystalline ZnO, rather surface smoothening0related grains’ coalescence was observed.

Biocompatible Diamond-Like Carbon (DLC) films were prepared by Pulsed Laser Deposition technique using the laser energy density of 10 J cm −2 on the graphite target. The surface of the grown film was modified during the deposition by bombardment with argon, xenon, nitrogen or oxygen ions. The ion energy (up to 150 eV) was changed by gun voltage and by ionic current. The films with high and low diamond/graphite content were prepared. Physical and mechanical properties of biocompatible DLC thin layers prepared by hybrid laser technology were studied. The composition of layers and the content trace elements were determined by the methods of Rutherford Backscattering Spectrometry and Particle Induced X-ray Emission. The content of sp 2 and sp 3 bonds was measured using X-ray Photoelectron Spectroscopy. For different energy of argon and oxygen ions the maximum of sp 3 bonds content was found (83.63% of sp 3 bonds for argon ions). All films were smooth, which was confirmed by profilometry and Atomic Force Microscopy measurements. Maximum roughness Ra and RMS was did not exceed 1 nm. The Younǵs and shear moduli were studied by Resonant Ultrasound Spectroscopy. The Young’s Modulus attained the value of 601 GPa and the shear Modulus attained the value of 253 GPa at the energy of 30 eV of Ar ions. The influence of ion bombardment on DLC film properties is discussed.

Hybrid laser-based technologies for deposition of new types of doped thin films are presented. The focus is on arrangements combining pulsed laser deposition (PLD) with magnetron sputtering (MS), and on the setup with two simultaneously running PLD systems (dual PLD). Advantages and disadvantages of both arrangements are discussed. Layers of different dopants concentration were prepared. Experience with deposition of chromium and titanium doped diamond-like carbon (DLC) films for potential coating of bone implants is presented. Properties of the layers prepared by both technologies are compared and discussed. The suitability of the layers for colonization with human bone marrow mesenchymal stem cells and human osteoblast-like cells, were also evaluated under in vitro conditions.

Silver doped diamond-like carbon layers were deposited by dual pulsed laser deposition using two KrF excimer lasers. The concentration of Ag, determined by XPS and WDS, moved from zero to ~ 10 at%. We found that the sp2/sp3 ratio, film roughness and the number of droplets (SEM and AFM) increased with increasing silver concentration. The sp3 content measurement (XPS) was influenced by ion cluster surface sputtering and varied from 71.0% (undoped DLC) to 36.2% (for 9.3 at% Ag). Transmission was measured on the scale from 200 nm to 1100 nm, and decreased with increasing silver content. An increase of Ag content has an effect on the decrease of the storage modulus (E′) and the indentation hardness (HIT). The highest values HIT = 51.9 GPa and E′ = 270.6 GPa were measured on a sample with 0 at% Ag. The lowest values HIT = 26.0 GPa and E′ = 180.2 GPa were measured on a sample of 9.3 at% Ag. Film adhesion was studied using the scratch test and was up to 20.8 N for the highest Ag concentration. The contact angle (CA) measurements for water showed that the CA of Ag-DLC films was higher (78°-98°) that of DLC film (77°). The surface free energy of DLC and of Ag-DLC was about 40 mJ·m− 2. Antibacterial properties were studied using gram positive and gram negative bacteria. The antibacterial effects increased with the Ag concentration and were ~ 99.9% after 24 h for the layers with the highest silver content (9.3 at%). Our results demonstrate that the Ag-doped DLC films are potentially useful biomaterials having both good mechanical properties and antimicrobial characteristics. Prime novelty statement Unique manufacturing technique dual pulsed laser deposition was applied on hydrogen-free diamond-like carbon doped by Ag including topological, physical and antibacterial characterization.

Diamond like carbon (DLC) layers have excellent biological properties for use in medicine for coating implants, but poor adhesion to biomedical alloys. The adhesion can be improved by doping the DLC layer by chromium, as described in this article. Chromium doped diamond like carbon layers (Cr‑DLC) were deposited by hybrid deposition system using KrF excimer laser and magnetron sputtering. Carbon and chromium contents were determined by wavelength dispersive X-ray spectroscopy. Mechanical properties were studied by nanoindentation. Hardness and reduced Young's modulus reached 31.2 GPa and 271.5 GPa, respectively. Films adhesion was determined by scratch test and reached 19 N for titanium substrates. Good adhesion to biomedical alloys and high DLC hardness will help to progress in the field of implantology.

Diamond-like carbon (DLC) and titanium-doped DLC thin films were prepared by unique hybrid system consisting of pulsed laser deposition, ion source (bombardment) and magnetron sputtering. The influence of deposition parameters (ion energies, deposition pressures and magnetron power) on composition and physical properties was studied. Composition and sp3/sp2 ratio were determined by XPS. sp3/sp2 ratio was in the range from 1.4 to 2.2 for undoped DLC and from 3.4 to 4.8 for Ti-DLC. AFM showed that the layers were smooth, but with small amounts of random droplets. The measurements of the contact angle and determination of surface free energy were made for water, diiodomethane and ethylene glycol. Hardness and reduced Young’s modulus varied from 20 to 31 GPa and from 182 to 276 GPa, respectively. Film adhesion was determined by scratch test; LC3 reached 23 N for DLC and 27 N for TiDLC. Optimization of sp3/sp2 ratio, hardness and adhesion to biomedical alloys will advance the DLC coatings usability in the field of implantology.

Diamond like carbon (DLC) and Ag-doped DLC (Ag-DLC) films were prepared by dual pulsed laser deposition using graphite and silver targets and two KrF excimer lasers. The silver concentration in the films was varied from 1.1 to 9.3 at. %. The surface topography was analysed by atomic force microscopy. The pure DLC was very smooth, but the roughness increased with rising silver content. Ethylene glycol, diiodomethane and deionized water were used to measure contact angles (CA). The measurements for water showed that the CA of Ag-DLC films (78–98°) was higher than that of the DLC film (77°). In order to understand the influence of incorporated Ag on the wettability, the surface energy and the protein adsorption as an indirect measure of the hemocompatibility were calculated. The surface energy of DLC and Ag-DLC films was same. The hemocompatibility was examined by the adsorption ratio of albumin/fibrinogen as an indirect method and improved with the increase of the Ag concentration. The antibacterial activity of the films were evaluated by bacterial eradication tests with Staphylococcus aureus and Pseudomonas aeruginosa at different incubation times. DLC and Ag-DLC films demonstrated good results against Staphylococcus aureus and Pseudomonas aeruginosa, meaning that DLC and Ag-DLC can be useful to produce coatings with antibacterial properties for biomedical devices such as sensors.

Diamond-like carbon (DLC) and Cr-doped diamond-like carbon layers were studied. DLC and Cr-DLC were deposited on silicon and titanium substrates (Ti-6Al-4V) by dual-pulsed laser ablation using two KrF excimer lasers and two targets (graphite and chromium). The composition was analyzed using wavelength-dependent X-ray spectroscopy. The Cr content increased from 2.2 to 17.9 at%. The topology and surface properties as roughness of layers were studied using scanning electron microscopy and atomic force microscopy. With the chromium concentration increased the roughness and the number of droplets. Carbon and chromium bonds were determined by Raman spectroscopy. With an increase in chromium content the I D/I G ratio increased. Mechanical properties of DLC films with various chromium content were evaluated. Hardness (reduced Young’s modulus) was determined by nanoindentation and reached of 51 GPa (309 GPa). Films adhesion was studied using scratch test and with concentration of chromium increased up to 20 N.

Two types of carbon-based films, namely diamond-like carbon (DLC) and ultrananocrystalline diamond (UNCD) films were comparatively investigated. The DLC films were prepared by pulsed laser deposition (PLD) without or with additional ion bombardment, the UNCD films by microwave plasma enhanced chemical vapour deposition. The films were characterized with respect to their topography and morphology (AFM, SEM) and bonding structure, e.g. fractions of sp3 and sp2 carbon atoms (XPS, FTIR and Raman spectroscopy). Finally, the wettability and the surface energies of both types of films were investigated with contact angle measurements as well as the antibacterial properties with two types of bacteria.

A hybrid PLD system with ion bombardment of films was developed. Growing DLC films were modified during the laser deposition (10 J cm−2) by argon ions with energy in the range from 40 eV to 210 eV and cathode current of 0.15 A and 0.5 A. The content of sp2 “graphitic” and sp3 “diamond” bonds was measured using XPS. Sp3 bonds changed from 60 % to 81 %. We found the highest sp3 content for energy of 40 eV. Hardness (and reduced Young’s modulus) were determined by nanoindentation and reached 49 GPa (277 GPa). Film adhesion was studied using the scratch test and was up to 14 N for titanium substrates. Relations among deposition conditions and measured properties are presented.

Ti-doped hydrogen free diamond-like carbon (DLC) layers of dopation up to ~25 at.% were prepared by dual beam pulsed laser deposition (PLD) using two excimer lasers. The arrangement allows continuous fine tuning of dopant concentration on a large scale and deposition flexibility. The layers were prepared on Si(1 0 0) and Ti6Al4V substrates at room temperature. The surface morphology, mechanical properties, bonds, composition, morphology of human osteoblast-like Saos-2 cells, their metabolic activity and production of osteocalcin, a marker of osteogenic cells' differentiation were tested. The films' composition changed after x-ray photoelectron spectroscopy (XPS) surface cleaning by argon clusters. Adhesion moved with Ti dopation from 4 N (DLC film) to 11 N (25 at.% of Ti in DLC). Creation of TiC was observed for higher Ti dopation. The contact angle and surface free energy stayed unchanged for higher Ti dopation. Saos-2 cells had the highest metabolic activity/viability on DLC with 10 at.% of Ti and on control polystyrene dishes on days 1 and 3. The Ti dopation improved the formation of vinculin-containing focal adhesion plaques in Saos-2 cells. Immunofluorescence staining revealed similar production of osteocalcin in cells on all tested samples.

Mechanical properties of diamond-like carbon thin films with various ratios of sp3/sp2 bonds were studied. The films were prepared in argon atmosphere (0.25 Pa) by laser deposition method for laser energy densities from 4 Jcm−2 to 14 Jcm−2. The sp2 and sp3 bonds were calculated by X-ray photoelectron spectroscopy. Films contained sp3 bonds up to 70 %. Surface properties as roughness and atomic force microscopy topology were measured. Hardness (and reduced Young's modulus) were determined by nanoindentation and reached of 30 GPa (203 GPa). Films adhesion was studied using scratch test and was up to 12 N for biomedical alloy (titanium substrates – Ti-6Al-4V). Relations among deposition conditions and measured properties are presented.