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Functional model for the synthesis of nanostructures of the given quality level

Suchikova Y. O., Kovachov S. S., Shishkin G. O., Pimenov D. O., Lazarenko A. S., Bondarenko V. V., Bogdanov I. T.

Archives of Materials Science and Engineering

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2021

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Vol. 107, nr 2

72--84

EN

Purpose: The aim of this paper is to develop a functional model for the synthesis of nanostructures of the given quality level, which will allow to effectively control the process of nanopatterning on the surface of semiconductors with tunable properties. Design/methodology/approach: The paper uses the IDEF0 methodology, which focuses on the functional design of the system under study and describes all the necessary processes with an accuracy sufficient for an unambiguous modelling of the system's activity. Based on this methodology, we have developed a functional model for the synthesis of nanostructures of the given quality level and tested its effectiveness through practice. Findings: The paper introduces a functional model for the synthesis of nanostructures on the surface of the given quality level semiconductors and identifies the main factors affecting the quality of nanostructures as well as the mechanisms for controlling the formation of porous layers with tunable properties. Using the example of etching single-crystal indium phosphide electrochemically in a hydrochloric acid solution, we demonstrate that the application of the suggested model provides a means of forming nanostructures with tunable properties, assessing the quality level of the nanostructures obtained and bringing the parameters in line with the reference indicators at a qualitatively new level. Research limitations/implications: Functional modelling using the IDEF0 methodology is widely used when process control is required. In this study it has been applied to control the synthesis of nanostructures of the given quality level on the surface of semiconductors. However, these studies require continuation, namely, the establishment of correlations between the technological and resource factors of synthesis and the acquired properties of nanostructures. Practical implications: This study has a significant practical effect. Firstly, it shows that functional modelling can reduce the time required to form large batches of the given quality level nanostructures. This has made it possible to substantiate the choice of the initial semiconductor parameters and nanostructure synthesis modes in industrial production from the theoretical and empirical perspective. Secondly, the presented methodology can be applied to control the synthesis of other nanostructures with desired properties and to reduce the expenses required when resources are depleted and the cost of raw materials is high. Originality/value: This paper is the first to apply the IDEF0 methodology to control the given quality nanostructure synthesis. This paper will be of value to engineers who are engaged in the synthesis of nanostructures, to researchers and scientists as well as to students studying nanotechnology.

2

Oxide crystals on the surface of porous indium phosphide

Suchikova Y. O., Bogdanov I. T., Kovachov S. S.

Archives of Materials Science and Engineering

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2019

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Vol. 98, nr 2

49--56

EN

Purpose: f this paper is to is to establish the patterns of oxide formation on the surface of indium phosphide during electrochemical etching of mono-InP. Design/methodology/approach: A porous surface was formed with the anode electrolytic etching. Morphology of the surface was studied with the help of scanning electron microscope JSM-6490. The analysis of chemical composition of porous surface of samples was also performed. Findings: It was shown that during the electrochemical etching of indium phosphide, oxide films and crystallites form on the surface. It has been established that crystalline oxides are formed mainly on the surface of n-type indium phosphide. Continuous oxide films are predominantly formed on the surface of p-InP. Research limitations/implications: The research was carried out for indium phosphide samples synthesized in the solution of hydrofluoric acid, though, carrying out of similar experiments for crystalline oxides on the surface of porous indium phosphide obtained in other conditions, is necessary. Practical implications: The study of oxide crystals on the surface of porous indium phosphide has great practical importance since it is the reproducibility of experimental results that is the main problem of modern materials science, the more nanoengineering. Oxides can significantly affect the properties of materials. On the one hand, oxides significantly affect the recombination properties of materials, this can impair the operation of semiconductor devices. On the other hand, oxide films can serve as a passivating coating for the surface of a porous semiconductor. Such an oxide property will be useful for the practical application of nanostructured indium phosphide. Therefore, questions of the conditions for the formation of semiconductor intrinsic oxides, their structure, and chemical composition, and also the effect of oxides on the physical and technical characteristics of materials are important. Originality/value: The patterns of oxide formation on the surface of indium phosphide during electrochemical etching are investigated in this work. It is shown for the first time that the structure of an oxide depends on the orientation of the surface of the semiconductor. It was shown that continuous oxide films are formed on the surface of p-InP, and oxide crystalline clusters are formed on the surface of n-InP.

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Modernizacja stanowiska wyznaczania naprężeń własnych w warstwie wierzchniej metali według koncepcji Waisman-Phillips

Brzezinski M. R., Mońka G., Nejman M.

Inżynieria Powierzchni

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2016

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nr 2

36--41

PL

W pracy opisano modernizację stanowiska do niszczącej metody wyznaczania naprężeń własnych w warstwie wierzchniej metali według koncepcji Waisman-Phillips. Naprężenia wyznaczane są pośrednio przez pomiar zmian krzywizny i strzałki ugięcia powierzchni próbek w wyniku usuwania warstw materiału metodą elektrochemicznego trawienia: po obróbce cieplnej, mechanicznej lub cieplno-chemicznej. Połączenia pomiaru odkształcenia za pomocą głowicy laserowej i sprzężony z tym komputerowy system przetwarzania i interpretacji wyników pomiarów umożliwia łatwe określanie wpływu różnych obróbek powierzchniowych na rzeczywisty stan własnych naprężeń w próbkach.

EN

This paper describes modernization of a stand for a destructive method of the determination of residual stresses in a surface layer of metals according to Waisman-Phillips conception. The stresses are determined indirectly by the measurement of an arrow of sag sample surface as a result of the electrochemical digesting of material layers after heat, mechanical or heat-chemical treatments. The combinations of the distortion measurement by means of a laser head and an interconnected computer system of processing and interpretation of measurement results enable the easy determination of the influence of different surface treatments on the real state of residual stresses in the samples.

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High and low voltage anodic etching of micro- and nanocrystalline Ti-based biomaterials

Adamek G., Jakubowicz J.

Inżynieria Materiałowa

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2010

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Vol. 31, nr 3

747-750

EN

Etching of the microcrystalline Ti, micro- and nanocrystalline Ti-6Al-4V was investigated. The process was run at 10, 100 and 150 V in H3PO4 electrolyte. Nanocrystalline alloy was prepared by mechanical alloying followed by powder metallurgical process. Surface morphology depends on the applied potential as well as etched material. The largest pores were obtained after etching of the nanocrystalline Ti-6Al-4V alloy, because large volume of the grain boundaries facilitates etching. The pore diameter reaches up to 60 um. Corrosion behaviour was investigated in Ringer's electrolyte. All samples, independently on theirs composition, etched at lowest 10 V shows best corrosion resistance. The corrosion resistance significantly decreases after etching at higher 100 or 150 V and according to increasing etching time and alloying elements or decreasing crystals size. For the nanocrystalline alloy, the large volume of the grain boundaries results in relatively poor corrosion resistance, which finally can be improved by anodic oxidation.

PL

Badano mikrokrystaliczny tytan oraz mikro- i nanokrystaliczne stopy Ti- 6Al-4V poddane elektrochemicznemu trawieniu. Proces trawienia prowadzono w potencjałach 10, 100 i 150 V w elektrolicie na bazie H3PO4. Stop nanokrystaliczny wytworzono za pomocą mechanicznej syntezy oraz metalurgii proszków. Morfologia powierzchni zależy od zastosowanego potencjału, jak również od struktury trawionego materiału. Największą porowatość obserwowano dla nanokrystalicznego stopu Ti-6Al-4V. Duża objętość granic ziaren sprzyja procesowi trawienia. Średnica wytworzonych porów dochodzi do 60 um. Badanie odporności korozyjnej prowadzono w płynie Ringera. Próbki trawione w niższym potencjale (10 V) wykazują lepszą odporność korozyjną, niezależnie od rodzaju obrabianego materiału. Odporność korozyjna była znacząco niższa po zwiększeniu potencjału trawienia (do 100 i 150 V), czasu procesu i ilości pierwiastków stopowych, a także wraz ze spadkiem wielkości ziaren (rys. 7 i 8, tab. 1). Duża objętość granic ziaren w przypadku stopu nanokrystalicznego skutkuje stosunkowo niską odpornością korozyjną, która jednak może zostać zwiększona przez anodowanie.

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Zmiany mikrostruktury w n-Si (111) podczas elektrochemicznego trawienia w warunkach braku iluminacji i w potencjale obwodu otwartego

Jakubowicz J.

Inżynieria Materiałowa

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2004

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R. XXV, nr 1

49-52

PL

Określono zachowanie się krzemu typu n w warunkach odbiegających od zwykle stosowanych w elektrochemicznym trawieniu w roztworze NH4F. W krzemie typu n z duża. ilością atomów domieszkowych (10^17 ÷ 10^19 cm^-3) w warunkach braku oświetlenia zaobserwowano rozszerzenie i przesunięcie zakresu powstawania porów do wyższych potencjałów. Efekt zmiany potencjału formowania porów jest tym większy, im mniejsza jest ilość atomów domieszkowych. Obniżenie ilości atomów domieszkowych o dwa rzędy wielkości z 2x 10^19 do 2x10^17cm ^-3 powoduje przesunięcie pierwszego piku prądowego i zakresu formowania porów o około 5 V. W krzemie z normalną ilością atomów domieszkowych 10^15 cm^-3 utrzymywanym w potencjale obwodu otwartego w czasie 2 min z oświetleniem powierzchni, na granicy pomiędzy tarasami powstały pory o regularnych kształtach. Obserwowano pory o głębokości do 13 nm i szerokości 2 ÷ 60 nm. Wyjściowa struktura tarasowa krzemu została zachowana, co świadczy o wysokiej stabilności tarasów.

EN

Electrochemical etching of n-Si in NH4F solutions was studied at unusually used conditions. In highly doped (10^l7-10^19) cm^-3 n-type silicon etched without illumination, the porous silicon formation was observed (Fig. 1, Fig, 2). The pore formation range was extended and moved toward higher potentials. With decreasing of a doping level from 2x 10^19 to 2 x 10^17 cm ^-3, porous silicon formation potential move towards higher potentials (5 V). In normally doped (10^15 cm ^-3) n-type silicon, kept for 2 min at open circuit potential under sample illumination conditions, the pores located at the border between terraces were observed too (Fig. 3). The pores had 13 nm depth and 2-60 nm width. The initial terraces of silicon surface were not changed, which confirm high stability of the terraces.

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Roughness of silicon after chemical and electrochemical etching

Jakubowicz J.

Inżynieria Materiałowa

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2004

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R. XXV, nr 3

215-217

EN

Chemical and electrochemical etching of silicon results in microstructural changes. Chemical H-termination of silicon in concentrated NH4F results in passivation of Si atoms by hydrogen. Surface is flat with atomic terraces of 0.3 nm height. Electrochemical etching in diluted NH4F results in pores or oxide formation. Roughness of the electrochemically etched silicon depends from molarity and pH of solution as well as potential and time of the processing.

PL

Chemiczne i elektrochemiczne trawienie krzemu powoduje zmiany mikrostruktury. Pasywacja chemiczna atomami wodoru w stężonym NH4F powoduje ujawnienie tarasowej struktury powierzchni o wysokości tarasów atomowych na poziomie 0,3 nm (Rys. 1). Trawienie elektrochemiczne w rozcieńczonym NH4F daje wynik w powstaniu porów (Rys. 2) lub tlenków (Rys. 5). Chropowatość elektrochemicznie trawionego krzemu zależy od molarności i pH elektrolitu, jak również potencjału i czasu procesu trawienia (Rys. 3, Rys. 4).