The results of this study show that creation of clusters from impurity nickel atoms almost completely suppresses generation of thermal donors within the temperature range 450 to 1200 °C. The composition of these clusters was determined using the technique of energy dispersive X-ray spectroscopy, which revealed that the typical cluster consists of silicon atoms (65%), nickel atoms (15%) and oxygen atoms (19%). Based on the experimental results, the authors have suggested that the nickel atoms intensively perform the role of getter for oxygen atoms in the course of clusterization. It was shown that the additional doping of silicon with nickel at T = 1100…1200 °C enables to ensure a sufficiently high thermal stability of its electrical parameters within a wide temperature range.

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The possibility of adjusting the operational parameters of industrial solar cells produced by the company Suniva based on monocrystalline silicon by means of additional diffusion doping with nickel in the temperature range 700–1200 °C has been investigated. It is shown that the optimal temperature of nickel diffusion is Tdiff = 800–850 °C. In this case the value of the maximum power Pmax increases by 20–28 % in relation to the parameters of the original industrial photocell. At diffusion temperatures Tdiff > 1000 °C, a sharp decrease in Pmax occurs, which is associated with an increase in the depth of the p–n-junction due to the distillation of phosphorus atoms during high-temperature diffusion of nickel. The positive effect of diffusion alloying with nickel on the electrophysical parameters of photocells is greatest in the case when the nickel impurity clusters are in the region of the p–n-junction, i. e. with diffusion alloying to the front side of the plate. The action of electrically neutral nickel clusters is less pronounced when they are located in the region of the isotypic p–p+ transition; in case of diffusion alloying with nickel in the opposite side of the plate.

The formation of clusters of impurity atoms in the crystal lattice of semiconductor materials is of great interest. The formation of nanoclusters with controlled parameters in the lattice of semiconductor materials can serve as the basis for the technology of creating and obtaining bulk nanostructured semiconductor material. This paper shows the experimental results obtained, as well as the proposed physical model of the structure of nickel atomic clusters. It is shown that the clusters move and migrate in the crystal lattice of monosilicon with an anomalously high diffusion coefficient of about c (D ~ 10 -9 cm 2 /s at T = 800°C). The structural composition of clusters of impurity atoms is determined, its structure and the mechanism of migration in the crystal lattice are proposed. Thus, it was found that it is possible to control the state of impurity atom clusters in the silicon crystal lattice, obtaining a new type of semiconductor materials with unique functional and properties using the cluster migration process. This makes it possible to create a new class of photonic materials with bulk superlattices based on semiconductors with ordered clusters, which has unique functionality for creating optoelectronic, nanoelectronic, photoelectric devices and sensors of physical quantities of a new generation.

Formation of complexes of impurity Mn atoms with impurity atoms of group VI elements (S, Se, Te) in the silicon crystal lattice has been studied. It has been experimentally found that formation of electrically neutral molecules with an ionic-covalent bond between Mn atoms and group VI elements takes place, which possibly leads to formation of new Si2BVI++Mn binary unit cells in the silicon crystal lattice. It has been shown that in the samples Si<S, Mn>, Si<Se, Mn> and Si<Te, Mn>, an intense complex formation occurs at the temperatures 1100, 820 and 650°C, respectively.