Clusters of impurity nickel atoms and their migration in the crystal lattice of silicon

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 cm2/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

A NEW WAY TO INCREASE EFFICIENCY SILICON PHOTOCELLS

It is shown that the effect of additional silicon doping with nickel weakly depends on the method of its introduction, and the presence of a nickel-enriched layer in silicon photocells leads to an improvement in their parameters. It was found that doping silicon with nickel prior to the formation of the p – n junction of the photocell is a more efficient method of its introduction

Clinical role of the “symptom-balloon” time in endovascular treatment of acute coronary syndrome with ST segment elevation

Aim. To investigate the clinical effectiveness of endovascular revascularization of the infarct-related coronary artery (IRCA) in regard to the “symptom-balloon” time, analyzing retrospective data on patients with acute coronary syndrome (ACS) and ST segment elevation (STE-ACS). Material and methods. The study included 164 patients with STE-ACS, who underwent selective coronary angiography (CAG) and transluminal balloon angioplasty (TLBAP) with coronary stenting. Based on the “symptom-balloon” time, all patients were divided into two groups. In Group I (n=78), the “symptom-balloon” time was <6 hours, while in Group II (n=86), it was 6–24 hours. Echocardiography (EchoCG) was performed at Day 1, 7, and 30. Results. The EchoCG data demonstrated a reduction in left ventricular (LV) systolic function. In Group I, LV systolic function significantly improved by Day 7: LV ejection fraction (EF) increased from 48,2% to 51,6% (p=0,0013). At Day 30, LV EF was 54,7% (p=0,001). In Group II, the increase in LV EF was not statistically significant (from 46,1% to 47,2%; p=0,2197).Conclusion. Urgent coronary revascularization in STE-ACS improved localLV contractility, due to the restriction of stunned myocardium areas. The speed of theLV contractility improvement after IRCA TLBAP/coronary stenting was strongly associated with the “symptom-balloon” time