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This paper presents application examples of atomic layer deposition method (ALD) adopted for production of multifunctional thin films for various usage such as passive, antireflection and transparent conductive films. First part of this paper introduces the mechanism of ALD process, in the rest of it, aluminum oxide (as passive and antireflection) and zinc oxide (as antireflection and transparent conductive) ALD thin films are presented. In the literature one can find reports on the use of the Al2O3 layer as passivating and ZnO layers as a transparent conductive oxide in diodes, polymeric and dye sensitized solar cells. In this article, the ALD layers were tested for their use in silicon solar cells, using their good electrical and optical properties. For examination of prepared thin films characteristics, following research methods were used: scanning electron microscope, atomic force microscope, X-ray diffractometer, ellipsometer, UV/VIS spectrometer and resistance measurements. By depositing a layer thickness of about 80 nm, the short-circuit current on the surface of the solar cell was increased three times while reducing the reflection of light. In turn, by changing the deposition temperature of the ZnO thin film, you can control its electrical properties while maintaining high transparency. The obtained results showed that the ALD method provide the ability to produce a high quality multifunctional thin films with the required properties.

The use of thin films in optoelectronic and photovoltaic devices is aimed at improving the physical properties of the substrate material. The modification of the surface of the silicon substrate is thus one of the greatest challenges in research on photovoltaic materials, in order to achieve even greater efficiency or better adapt their properties depending on the application. The technologies of applying layers vary depending on the effect to be obtained and the material from which the layer is formed. In practice, the most common method is chemical vapor deposition and physical vapor deposition, and the most commonly applied optical materials are SiO2, TiO2 and Si3N4.This paper presents the results of investigations on morphology and optical properties of the prepared aluminium oxide thin films. Thin films were prepared with use of sol-gel spin coating method. Surface morphology studies were carried out using an atomic force microscope. To characterize the surface of the thin films, 3D images and histograms of the frequency of individual inequalities were made. In order to characterize the optical properties of Al2O3 thin films, the reflectance and light transmission tests were performed using a spectrophotometer. Optical constants were determined using a spectroscopic ellipsometer. Results and their analysis show that the sol-gel method allows the deposition of homogenous thin films of Al2O3 with the desired geometric characteristics and good optical properties. Uniform, continuous thin layers with a roughness not exceeding a few nanometres were deposited. Their deposition enabled to reduce the reflection of light from the polished substrate below 15% in a wide range (425-800nm) while maintaining high transparencies (over 90%). The obtained results causes that mentioned thin films are good potential material for optics, optoelectronics and photovoltaics.

The main goal of carried out tests were the impact of physicochemical properties of surface layers on the course of processes taking place on the surface of implants made of metallic biomaterials used in the bone system. As a precursor of ZnO, diethylzinc (DEZ) has been used, which reacted with water enabling the deposition of thin films. The chamber temperature was as follows—T= 200°–300 °C. The number of cycles was 500, 1000, and 1500. In the first stage, pitting corrosion test was carried out. Corrosion resistance has been tested under conditions simulating tissue environment. Moreover, the created layers were tested using electrochemical impedance spectroscopy (EIS). The conducted electrochemical tests showed the beneficial effect of the ZnO layer on the substrate made of 316 LVM steel, as evidenced by the obtained parameters describing the corrosion resistance. Furthermore, tests were performed on mechanical properties (scratch test), surface morphology (SEM and AFM method), and physical properties (wettability and thickness layers) for samples with different surface treatments. The investigations of the surface morphology of the applied ZnO layer using the ALD method showed a tendency to inherit the substrate independently of the used application parameters. On the other hand, the tests of adhesion to the substrate showed that the number of cycles of the application process has a fundamental impact on the adhesion of the applied layer to the substrate. Summarizing tests have clearly shown that the number of cycles and temperature in the case of the ZnO coating is significant and positively influences the increase of electrochemical, mechanical, and physical properties of layers.