The fabrication of 45°micromirrors by silicon anisotropic etching in potassium hydroxide (KOH) and tetramethylammonium hydroxide (TMAH) solutions containing organic additives is investigated in this paper. The reflective planes are formed by {110} sidewall planes inclined at 45°towards the Si (100) wafer. Isopropyl alcohol and Triton X-100 surfactant are used as additives, because they are supposed to provide the etch rate ratio R(100)/R(110) [ 1, which is necessary for {110} sidewalls development. The fabricated spatial microstructures with 45°sidewalls are examined in terms of the {110} surface roughness and the quality of the {110} sidewall profile. The KOH solution saturated with the alcohol gives the striped {110} surface, though the stripes almost disappear after addition of Triton surfactant to KOH and TMAH etchants. The 45°sidewall profiles fully defined by {110} planes are obtained in KOH as well as TMAH solutions containing additives. The measurements of micromirrors' reflectivity indicate that replacement of the alcohol by Triton surfactant in the KOH solution reduces the optical power loss caused by the reflection. The achieved reflectivity is comparable with the one obtained by etching in the TMAH solution with surfactant.

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This publication presents experimental measurement methodology which allows to determine the characteristics of sensitivity planar differential interferometer. To confirm data reliability additional measurements were done such as simulations in OptiBPM software by Optiwave. Curves received from two methods: experimental and theoretical, were summed up and compared. Conclusions were made on their basis, for example the influence of used wavelengths or refractive index of single mode waveguide cladding on curves of sensitivity differential interferometer using planar waveguide received from the ion exchange method.

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In this study, the authors deposited silicon oxynitride films by Radio Frequency Plasma Enhanced Chemical Vapour Deposition (RF PECVD) method. The research explores the relationship between the deposition process parameters and the optical properties of the deposited SiO x N y films. The optical constants of SiO x N y films were measured and calculated by spectroscopic ellipsometry method. Additionally, the authors investigated the possibility of controlling the deposited film composition by the flow ratio of different gaseous precursors: ammonia (NH 3 ), diluted silane (2%SiH 4 /98%N 2 ), nitrous oxide (N 2 O) and nitrogen (N 2 ). The gas mixture introduced to the working chamber during the growth of the film has the influence on the Si-O and Si-N bonds formation and the ratio between these bonds determines the refractive index of the deposited film.

In this paper, the methodology for design of the system consisting of chromatic confocal displacement sensor integrated with an optical laser head was presented. Furthermore, the results of experimental characterization of optical components of the laser head were also included in the numerical analysis. The designed chromatic confocal displacement sensor was analyzed as an assembly of components widely available on the optical market. Nevertheless, the main goal of the numerical optimization was to determine the influence of individual components of the optical path of the system on its parameters, i.e., measuring range, FWHM of the characteristic spectral peak, and intensity that reaches the detector. The optimized solution was characterized in order to determine the calibration curve, as well as other important application parameters of the system. Moreover, taking into consideration the integration aspect the caustic of the laser beam shaped by the laser head was measured. Finally, the versatility of the system was presented and discussed.

Three methods of AlN layers oxidation: dry, wet and mixed (wet with oxygen) were compared. Some physical parameters of oxidized thin films of aluminum nitride (AlN) layers grown on silicon Si(1 1 1) were investigated by means Energy-Dispersive X-ray Spectroscopy (EDS) and Spectroscopic Ellipsometry (SE). Three series of the thermal oxidations processes were carried out at 1012°C in pure nitrogen as carrying gas and various gas ambients: (a) dry oxidation with oxygen, (b) wet oxidation with water steam and (c) mixed atmosphere with various process times. All the research methods have shown that along with the rising of the oxidation time, AlN layer across the aluminum oxide nitride transforms to aluminum oxide. The mixed oxidation was a faster method than the dry or wet ones.

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