Abstract A conductive boron-doped diamond (BDD) grown on a fused silica/quartz has been investigated. Diamond thin films were deposited by the microwave plasma enhanced chemical vapor deposition (MW PECVD). The main parameters of the BDD synthesis, i.e. the methane admixture and the substrate temperature were investigated in detail. Preliminary studies of optical properties were performed to qualify an optimal CVD synthesis and film parameters for optical sensing applications. The SEM micro-images showed the homogenous, continuous and polycrystalline surface morphology; the mean grain size was within the range of 100-250 nm. The fabricated conductive boron-doped diamond thin films displayed the resistivity below 500 mOhm cm-1 and the transmittance over 50% in the VIS-NIR wavelength range. The studies of optical constants were performed using the spectroscopic ellipsometry for the wavelength range between 260 and 820 nm. A detailed error analysis of the ellipsometric system and optical modelling estimation has been provided. The refractive index values at the 550 nm wavelength were high and varied between 2.24 and 2.35 depending on the percentage content of methane and the temperature of deposition.
Maciej Kraszewski and Robert Bogdanowicz
In situ monitoring of the thickness of thin diamond films during technological processes is important because it allows better control of deposition time and deeper understanding of deposition kinetics. One of the widely used techniques is laser reflectance interferometry (LRI) which enables non-contact measurement during CVD deposition. The authors have built a novel LRI system with a 405 nm laser diode which achieves better resolution compared to the systems based on He-Ne lasers, as reported so far. The system was used for in situ monitoring of thin, microcrystalline diamond films deposited on silicon substrate in PA-CVD processes. The thickness of each film was measured by stylus profilometry and spectral reflectance analysis as a reference. The system setup and interferometric signal processing are also presented for evaluating the system parameters, i.e. measurement uncertainty, resolution and the range of measurable film thickness.
Łukasz Pietruszyński, Alicja Olszewska and Robert Bogdanowicz
The goal of this paper is to assess the impact of reservoirs on the water quality of watercourses in the urbanized catchment. To realize this goal Oruński Stream catchment was characterized with particular emphasis on retention reservoirs located within the catchment. Studies carried out were to show that these retention reservoirs change the water quality of the stream flowing through it and what the direction of these changes is.
Bartłomiej Dec, Mateusz Ficek, Michał Rycewicz, Łukasz Macewicz, Marcin Gnyba, Mirosław Sawczak, Michał Sobaszek and Robert Bogdanowicz
The main subject of this study are molecular structures and optical properties of boron-doped diamond films with [B]/[C]ppm ratio between 1000 and 10 000, fabricated in two molar ratios of CH4-H2mixture (1 % and 4 %). Boron-doped diamond (BDD) film on the fused silica was presented as a conductive coating for optical and electronic purposes. The scanning electron microscopy images showed homogenous and polycrystalline surface morphology. The Raman spectroscopy confirmed the growth of sp3 diamond phase and sp2carbon phase, both regular and amorphous, on the grain boundaries, as well as the efficiency of boron doping. The sp3/sp2ratio was calculated using the Raman spectra deconvolution method. A high refractive index (in a range of 2.0 to 2.4 at λ= 550 nm) was achieved for BDD films deposited at 700 °C. The values of extinction coefficient were below 1.4 at λ= 550 nm, indicating low absorption of the film