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Оne of the promising materials in solid state electronics is the AlN compound. A wide range of semiconductor devices are produced from it, such as photodetectors, LEDs, piezoelectric converters, etc. But the widespread use of products based on AlN prevents low manufacturability designs based on it. In this regard, the development of new technologies for the production of devices based on AlN is relevant.The work is devoted to the study of thin AlN films obtained by plasma spraying from AlN powder. The review of existing technologies of production of thin films AlN is carried out.Their advantages and disadvantages are discussed. Information on the modernization of the VUP-5 installation, which allowed to spray the AlN film from the powdered state, is given.One of the significant advantages of the process developed in this work is that the substrate is heated to temperatures no higher than 300 oC, which in turn allows to combine this technology with the technology of silicon semiconductor devices.As a result, films with a thickness of 200 nm on various substrates were obtained and their surface structure was studied. It is shown that AlN films deposited on single crystal substrates such as diamond and silicon have the least roughness, while films on sitall have the worst roughness.The transmission spectra of the obtained AlN films were investigated by IR spectroscopy. With their help, it was shown that a polycrystalline AlN layer oriented in the crystallographic direction 002 is formed on the substrate. The piezoelectric properties of the obtained films were investigated by scanning probe microscopy. It is shown that their piezoelectric coefficient d33 is 60% of the value for a single-domain single-crystal sample for a diamond substrate, which indicates a sufficiently high quality of the resulting film.It is concluded that, although the quality of the layers strongly depends on the substrate, nevertheless, they exhibit a significant piezoelectric effect, which allows the use of this method for the manufacture of piezoelectric sensors, ultrasonic emitters, etc.

The paper considers position-sensitive photodetectors (PSP), which are designed to detect the source of electromagnetic radiation in the optical range and determine the coordinates of the irradiated area in real time, as well as to track moving optical objects. In particular, data are presented on photodetectors based on photosensitive epitaxial CdSe/mica layers with an unconventional layout and switching of electrical contacts. The output signal of such PSP is the transverse potential difference that appears between its two contacts after exposure of one of the areas of the photodetector. These PSPs can be an alternative or competition to existing photocells due to high accuracy, speed, ease of manufacture and low cost. But there are significant obstacles for their wide application. First, it is an analog type of output signal, which prevents its further processing. And, second, it is difficult to calibrate “manually” a newly made photosensor: it takes a long time associated with the accumulation and processing of large amounts of data. The introduction of computer technology and the creation of an information-measuring system allow us to process the output signals of such photodetectors with high accuracy and speed in real time. To solve this problem we have developed a stand for the study of position-sensitive photodetectors, which is presented in this paper. This stand allows digitizing the signal received from the photodetector, in real time, with high accuracy to determine the coordinates of the irradiated area on the photodetector and explore its characteristics such as the specified value of the dark current of the photodetector, light current at a certain illumination, and output voltage. At this stand, position-sensitive photodetectors based on the CdS/mica system were studied. It is shown that the characteristics and parameters of photoreceivers measured on this stand coincide with theoretical ones, within the error limits. Recommendations on the use of the standare given.