Results are reported on an investigation of IR−absorption spectra of shallow donors and acceptors in high−purity single crystals of stable 28Si(99.99%), 29Si(99.92%) and 30Si(99,97%) silicon isotopes grown by zone melting. The content of residual boron, phosphorus and arsenic impurities Nhas been determined in the single crystals with a detection limit of 1 · 1012 at./cm3, 4 · 1011 at./cm3 and 1 · 1012 at./cm3, respectively. IR−spectroscopy results on the content of shallow donors and acceptors are in a good agreement with the data on concentration of uncompensated charge carriers obtained by Hall measurements. The parameters of absorption lines for the boron and phosphorus impurities in the single crystals of silicon isotopes have been studied. We show that a change in the isotopic composition of silicon leads to a shift in the energy spectrum of shallow impurity centers towards the high−energy range with an increase in the atomic mass of the isotope.

The electronic, optical and mechanical properties of heterosystems with Ge1−xSix solid solution films on the GaAs
(x = 0–0.04) and Si (x = 0.75) substrates have been studied. We used electroreflectance modulation spectroscopy for the films and the substrates, classical spectroscopy in the intrinsic absorption region of the films and mechanical stress measurements in the films and in the substrate. We show that the Ge1−xSix films can change composition with the formation of other solid solution structures both during film deposition
and under γ−irradiation. There is a possibility to reduce the mechanical stresses, to improve the electronic parameters of the films and the substrates at the interface, and to produce heterosystems without bending deformation.

Specific features of impurity distribution in multisilicon crystals grown from refined metallurgical silicon by the vertical Bridgman−Stockbarger method have been studied. The chemical composition of metallurgical silicon and multisilicon ingots grown under varying crystallization conditions have been analyzed by mass spectrometry with inductively coupled plasma (ICP−MS) and X−ray spectral electron probe microanalysis (RSMA). The size and distribution nature of microinclusions on the polished etched surfaces and chips of multisilicon crystals have been studied. We have revealed multicomponent microinclusions up to 100 micron in size in the multisilicon ingots grown at high crystallization speeds (1.5 cm/h) and low−component microinclusions one micron in size in the multisilicon ingots grown at a crystallization speed of from 0.5 to 1 cm/h.

The physical models and numerical algorithms allowing one to accurately simulate advanced technological processes, such as low−energy ion implantation and rapid thermal processing (RTA) are presented. A software system on the basis of these models has been designed and integrated into the microelectronics device and process modeling system Silvaco ATHENA. It enables the use of models and calculation
methods alternative to those implemented in the well−known software products, mainly for solving the problems with shallow depths of doped regions

Polycrystalline 3C−SiC films have been grown on silicon substrates by CVD method using Methyltrichlorosilane thermal dissociation in a hydrogen atmosphere at temperatures of 1000—1250 °С. The process parameters providing for the growth of homogeneous 3C−SiC layers with smooth surfaces and high adhesion have been determined. The defect structure of the silicon substrate with deposited 3C−SiC film has been investigated by X−ray topography. All the projector topographic patterns show that the elastic stress contrast inherits exactly the film morphology. The subsurface elastic stress fields in the substrate decrease with an increase in the 3C−SiC film growth temperature. We show that the 3C−SiC film heterostructure is highly sensitive to heat treatment.

Results on the influence of Ge ion implantation into pyrogenic SiO2 on radiation charge accumulation are presented. Ge embedding in the silicon dioxide/ silicon system has been analyzed theoretically. We show that Ge ion embedding in the stoichiometric silicon dioxide at the silicon dioxide/ silicon interface or forming Ge nanoclusters in the SiO2 bulk provide an energetic advantage.

Ti, Al, Ni, Cr and Au metal films have been deposited onto silicon (100) n−type 100 mm substrates by thermal evaporation technique. The film thickness and sheet resistance distributions have been measured. We show that the increase in the sheet resistance towards the substrate edge occurs due to both a decrease in the film thickness and an increase in the metal resistivity.

We have investigated the fabrication of AuxTi100−x—nSi (where x is 10; 36; 87) and PbxSb100−x—nSi (where x = 52; 70; 87) Schottky diodes and the electrical properties of AuxTi100−x—nSi (where x = 10; 36; 87) and PbxSb100−x—nSi (where x = 52; 70; 87)Schottky diodes. The Au36Ti64, Pb52Sb48 alloy film has an amorphous structure, while the other films are polycrystalline. We have determined Schottky barrier height depending
on the composition and structure of the metal films and found that the barrier height is quite sensitive to the composition of the metal alloy. We show that the electrical properties of the AuxTi100−x—nS and PbxSb100−x—nSi Schottky diodes depend on the composition and structure of the metal films.

This paper presents the method for obtaining hidden layers of porous and nonporous silicon and the results of a study of their structure depending on the conditions of electrochemical anodic etching and the parameters of the samples. We show that the formation of hidden layers during high voltage etching may occur as a result of the establishment of avalanche breakdown in the local area of the clamping contact at the beginning of etching, wherein etching occurs during the avalanche ionization of the major carriers as a result of the breakdown at the sample edges. The separating upper layer is not disturbed and retains the initial crystalline structure.
The critical role in the formation of hidden defect layers belongs to the point defects and electrolytic hydrogen which form during silicon etching.

Results of experimental work with nanosized silicon (NcSi) samples which are not degraded under the action of intense laser radiation have been obtained. We show that that a significant increase in the intensity of the
photoluminescence signal from NC may be caused by the structural features of their formation and by the presence of a thin SiO2 layer on the surface of the nanocrystals.

The formation of porous structures in sol−gel systems based on silicon oxide and metal oxides, i.e. cobalt and tin, has been studied. We show that the investigation of metal oxide nanomaterials by the thermal desorption method allows developing the optimum process conditions for obtaining patterns having the highest specific surface area.

The films have been deposited on the silicon subtracts with the (111) and (100) orientations by thermal evaporation of SiO powder and carbon implanted with doses of 6 · 1016 to 1,2 · 1017 cm−2 followed by annealing in nitrogen at 1100 oC. Diffraction studies of these structures confirm the occurrence of a preferred orientation in the nanocrystals during high temperature thermal annealing, controlled by the substrate orientation. It was possible to detect the existence of two arrays of silicon nanocrystals in the dielectric matrix, with one having a smaller average size of 5—10 nm and a lattice parameter close to that of crystalline silicon, and the other one having a large size of 50—100 nm and a greater lattice parameter. We have estimated the carbon implantation doses for which the large size nanocrystals (> 50 nm) do not form. This dose is 6 · 1016 cm−2 for the (111) substrates and 9 · 1016 cm−2 for the (100) ones.

Results on gradient planar optical waveguides on the basis of fluorinated silica glasses fabricated in low pressure HF−plasma are presented. The optical characteristics are investigated and possible applications of planar gradient waveguides in multi−channel optic couplers are considered.

The paper describes a complex study of chemically etched porous silicon layers and the relationship between etching parameters and porous layer properties. We show that the conductivity of porous silicon is similar to that of amorphous silicon. Chemical etching allows creating porous layers with the same intensity of photoluminescence and absorption as for anodically etched porous silicon.