The paper presents the results of a study of the field dependences of charge losses, silicon diffusion detectors that allow identifying single atoms and their clusters acting as charge carrier capture centers. In electric fields E > 1470 V/cm, there is an effective decrease in the capture processes, which manifests itself in the form of straightening of the field dependences of charge losses and in the narrowing of spectral lines. Effects - an ultrasonic field with an intensity of I * = 0.4 W / cm2 and a frequency of f = 15 MHz, on samples for a time t £ 45 minutes, leads to an increase in the amplitude of the signal. It is established that ultrasonic exposure leads to a decrease in charge loss, drift time and an improvement in the energy resolution of detectors. It should also be noted that fluctuations of the impurity relief in the Si-p-type volume are smoothed out after low-power ultrasonic waves pass through it for a long time, as evidenced by a significant decrease in the effective size of local defect clusters.

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In this work, the parameters of Schottky diodes obtained by sputtering chromium on silicon and annealed at 900÷1100°C. were investigated. Experimental studies of Schottky contacts based on silicides have an all-microscopic analysis of the physical and chemical properties of the layers and an analysis of the electrical behavior of the system. The Schottky model assumes that surface states are located on the border between the transition layer and silicon. Using measurements of direct and inverse volt-amperage characteristics (VAC), values of the height of the effective Schottky barrier, the rate of change in the height of the barrier, as well as the value of the density of surface states, the thickness of the transition layer were obtained and the tunneling process was considered. The temperature dependencies of electrical conductivity are given and the course of the curve is analyzed. The obtained VAC is explained by the model of thermionic emission of the Schottky theory. Height of a barrier to contact chrome-silicon silicide which is equal to 0.65 eV is determined, and the factor of ideality was close to unit. The number of steps required by the charge carriers to overcome the potential barrier is determined. It is described that the current transfer mechanism is associated with the presence of surface states at the interface, as well as the occurrence of lattice mismatch and the difference in thermal coefficients. Diode illumination by LED confirms the effect of surface states on VAC. An increase in the surface states of photogenerated holes is shown. It has been shown that the existence of surface states affects the change in the height of the potential barrier, the amount of bending of the zones, and also determines that the predominant transfer mechanism is a tunneling multistage mechanism.

The currents of n-p junctions and polarization effects caused by the capture processes of diffusion Si-receivers (detectors) of radiation exposed by ultrasound have been analyzed in this work. It was found that there are local concentrations of impurity atoms with an effective size l>6μm30μm in Si-n-p radiation receivers. They determine the behavior of the signal amplitude in different intervals of electric and temperature fields. It was found that at Е>1500V/cm and T>168K, the efficiency of collecting nonequilibrium charge carriers significantly increases and doublets of spectral α-lines and “humps” disappear at the temperature dependences of the signal amplitude. The main physical processes and mechanisms that determine the appearance of the phenomenon of "polarization" of Si-n-p-detectors were investigated. This phenomenon is caused by the existence of local gold atoms, which arise in the process of manufacturing technology of Si-n-p-receivers and act as effective trapping centers.