Zbigniew Swiatek | Polish Academy of Sciences (original) (raw)

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Papers by Zbigniew Swiatek

Microstructure and mechanical properties of NiAlV alloys of the composition belonging to the pseu... more Microstructure and mechanical properties of NiAlV alloys of the composition belonging to the pseudo-binary Ni3Al-Ni3V cross-section were investigated. The samples were prepared by the cold crucible levitation melting (CCLM) and by re-melting and crystallizing in the small volume copper mould. The phase composition of the samples, with should result from the eutectoidal decomposition was not found. Instead the Ni3(Al,V) and Ni(Al,V) solid solution or seldom disordered solid solution were retained due to the relatively high cooling rates. In the compression test the NiAlV alloys crystallized in the copper mould revealed high ductility and strength.

Archives of Metallurgy and Materials, 2013

Some attention in physical metallurgy is devoted to the mechanisms of decomposition of the disord... more Some attention in physical metallurgy is devoted to the mechanisms of decomposition of the disordered phases via eutectoid transformation accompanied by the atomic ordering. In case of the non-pearlitic modes of transformation this concerns intermetallic phases of the general description A3B-A3C. The application of intensive deformation like HPT may introduce opposite mechanisms introducing some degree of the metastable disordered phase structure at room temperature. The paper presents results of the phase composition and microstructure studies of the alloys of composition Ni75AlxVy (where x =15, 10, 5 and y =10, 15, 20), which undergo the solid-state eutectoid decomposition at temperature 1281 K, in the equilibrium conditions. The alloys achieved by the cold crucible levitation method were later intensively deformed with the method of high pressure torsion (HPT). The alloys after HPT revealed homogenous, metastable L12 (Ni3Al) structure in place of the eutectoid product L12-D022. T...

Semiconductor Science and Technology, 2020

The Hall-effect (with mobility spectrum analysis) and capacitance measurements were combined with... more The Hall-effect (with mobility spectrum analysis) and capacitance measurements were combined with transmission electron microscopy for the study of molecular-beam epitaxy-grown n-type Hg1-xCdxTe (x = 0.22) films subjected to various operations used in the fabrication of p +-n photodiode structures. The operations included arsenic ion implantation, activation annealing and extra annealings aimed at investigation of the details of the p +-n junction formation. A detailed characterization of p+-type layers formed by the implantation was done. A high degree of arsenic activation by activation annealing was demonstrated, along with the annihilation of implantation-induced extended (dislocation loops) and quasi-point defects, and the disappearance of electrically active centres associated with them. The annealing was also shown to cause the activation of residual acceptors, changing the degree of electrical compensation in the n-‘base’ of some of the p +-n structures.

Acta Physica Polonica A, 2011

Inorganic Materials, 2000

Materials Science Forum, 2000

ABSTRACT The utilisation range of deposited coatings strongly depends on their structure, in part... more ABSTRACT The utilisation range of deposited coatings strongly depends on their structure, in particularl on the crystallographic texture. The aim of the work is to analyse the texture and its inhomogeneity in the normal direction to such coating. The influence of the substrate texture on the formed layer orientation in the deposition process with assumed electrochemical parameters is analysed. Copper coatings electrodeposited on the textured copper substrate as a simple model system was examined. The copper layer of 10μm thickness was deposited from an acid sulphate bath. To ensure constant and controlled hydrodynamic conditions, a system with a potentiostatically power supplied rotating disc electrode was used. The texture analysis was performed on the basis of the back-reflection pole figures and of ones with a constant information depth, measured by means of x-ray technique. The non destructive method allowed to analyse the texture for different chosen areas of the deposited layer. The presented results show the existing texture inhomogeneity depending on the electrodepositing process. The texture of the substrate reveals a strong influence on the texture of the formed Cu layer in its near-interface area (texture inheritance phenomenon). As far as depositing front withdraws from the substrate surface, the texture proceeds to a one component of axis type of (111)[uvw]. It is illustrated in the three-dimensional texture functions given for the chosen near-surface layers of examined sample.

Solar Energy Materials and Solar Cells, 2002

Double porous silicon (d-PS) layers formed by acid chemical etching on a top surface of n+/p mult... more Double porous silicon (d-PS) layers formed by acid chemical etching on a top surface of n+/p multi-crystalline silicon solar cells were investigated with the aim to improve the performance of standard screen-printed silicon solar cells. First a macro-porous layer is formed on mc-Si. The role of this layer is texturization of surface. Next, the cells have been manufactured using standard technology based on screen-printing metallization. Finally, a second mezo-porous layer in n+ emitter of cell has been produced. The role of this PS layer is to serve as an antireflection coating. In this way, we have obtained d-PS layers on these solar cells. The paper present observation of d-PS microstructure with SEM as well as measurements of its effective reflectance at the level of 2.5% in the 400–1000nm length wave range. The efficiency of the solar cells with this structure is about 12%.

$Research paper thumbnail of X-ray diffraction characterization of microdefects in silicon crystals after high-energy electron irradiation$

physica status solidi (a), 2011

Page 1. Copyright line will be provided by the publisher pss-Header will be provided by the publi... more Page 1. Copyright line will be provided by the publisher pss-Header will be provided by the publisher 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 ...

physica status solidi (a), 2007

Journal of the Electrochemical Society, 2014

ABSTRACT The conditions for manganese with tin electrodeposition from aqueous citrate electrolyte... more ABSTRACT The conditions for manganese with tin electrodeposition from aqueous citrate electrolytes were studied. Partial polarization curves were determined. The influence of applied potential, electrolyte composition and pH level, hydrodynamic conditions and quantity of charge passed, on the electrodeposition of Sn-Mn layers were determined. The surface composition of deposits was ascertained by chemical analysis (WDXRF). The morphology of coatings was studied by SEM. The phase composition of Sn-Mn samples was determined by X-ray diffractometry and Raman spectroscopy. The electrolysis parameters allowing electrodeposition of Sn-Mn coatings containing various amounts of Mn (in the range from about 0.5 wt% to 42 wt%) were selected. The morphology of deposits depends significantly on the content of manganese and on the parameters of electrolysis. The surface morphology of samples with Mn content of about 27 wt% is not uniform, two types of areas with significant differences in chemical composition are observed. XRD studies indicate that four crystallographic phases are formed in the deposits (β-Sn),MnO,Mn(OH)2, andMnSn2, while Raman spectroscopy revealed also the presence of α-MnO2, MnOOH, and SnO2, which are the products of chemical processes taking place simultaneously with electrolysis. The mechanism of the co-deposition of manganese with tin has been proposed.

Archives of Metallurgy and Materials, 2007

X-ray diffraction methods as well as atomic force microscopy (AFM) and secondary ion mass spectro... more X-ray diffraction methods as well as atomic force microscopy (AFM) and secondary ion mass spectroscopy (SIMS) were used to study the controlled doping and structural homogeneity of HgCdTe epitaxial layers. The investigated layers were obtained by the evaporation-condensation-diffusion (ECD) method in the process of isothermal growth. Two types of substrates for CdHgTe ECD growth were used: (110) and (111) CdTe monocrystals with As ion implanted surface layer at a dose of 1×1015cm−2 and an energy of 100 keV. Structural changes in damaged areas of CdTe crystals that arise at the ion beam implantation and the influence of radiation defects on the quality of obtained layers are analyzed.

Thin Solid Films, 2002

ABSTRACT The possibility of using ITO–pCdTe and Au–nCdTe compounds for photovoltaic purposes was ... more ABSTRACT The possibility of using ITO–pCdTe and Au–nCdTe compounds for photovoltaic purposes was investigated. For n-CdTe samples under AM2 illumination at 300 K, an efficiency of 13% was achieved. 2002 Elsevier Science B.V. All rights reserved.

Thin Solid Films, 2002

The results of controlled doping of CdxHg1−xTe epitaxial layers are presented. The investigated l... more The results of controlled doping of CdxHg1−xTe epitaxial layers are presented. The investigated layers were obtained by the evaporation–condensation–diffusion method in the process of isothermal growth. The process of auto diffusion from the solid phase was investigated. This process consists in the diffusion of As dopants from CdTe substrate into the grown epitaxial layer. Two types of CdTe substrates, uniformly

Thin Solid Films, 2000

ABSTRACT Time-dependent changes of electrical properties are investigated in the range of relativ... more ABSTRACT Time-dependent changes of electrical properties are investigated in the range of relative low heating temperatures (T=320 to 450 K) for undoped p-CdTe grown by various methods. It is established that the character and direction of the observed changes depend on the level of uncontrolled impurities (Cu preferably), their charge state and the association degree of impurities with intrinsic (VCd) defects. CdTe:Ge (Sn,Pb) crystals are characterized with a high thermostability of electrical properties.

$Research paper thumbnail of New X-ray diffraction method for materials science$