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1

Badanie powierzchni materiałów ceramicznych metodą spektrometrii masowej jonów wtórnych

Tuleta M.

Materiały Ceramiczne

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2014

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T. 66, nr 2

126--128

PL

Profile głębokościowe przypowierzchniowego obszaru szkła sodowo glinokrzemianowego i warstwy diamentowej zostały otrzymane metodą spektrometrii masowej jonów wtórnych (SIMS). Profile pokazały zależność od wiązki jonów pierwotnych tlenu i cezu. Efekt ten jest wyjaśniany różnym mechanizmem modyfikacji powierzchni poddawanej działaniu jonów pierwotnych.

EN

Depth profiles of the near-surface region of sodium aluminosilicate glass and diamond film were obtained by the secondary ion mass spectrometry method. The profiles showed the dependence on oxygen and cesium ion beams. This effect is explained by various modification mechanisms of the surface treated with primary ions.

2

The application of CVD diamond films in cyclic voltammetry

Torz-Piotrowska R., Wrzyszczyński A., Paprocki K., Screiber M., Uniszkiewicz C., Staryga E.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

486-491

EN

Purpose: The main purpose of these studies was to show the applicability of CVD (Chemical Vapour Deposition) diamond layer in electrochemistry and to work out the technology of manufacturing diamond electrodes. Design/methodology/approach: The diamond films were deposited on tungsten substrate by HF CVD technique, and then, their quality was checked by Raman spectroscopy. It was shown, using Cyclic Voltammetry (CV) measurements, that un-doped diamond films are chemically stable in aqueous solutions. Findings: The results of cyclic voltammetry measurements show that diamond electrode on tungsten substrate is electrochemically stable in aqueous solutions over a wide potential range (-3000 mV to 2000 mV). The Raman spectra confirmed the good quality of obtained diamond layer. Research limitations/implications: In particular, it was shown that diamond electrode showed a wide potential window, very low background current, chemical and physical stability. Practical implications: Presented results showed that CVD diamond films can find application in production of diamond electrodes for electrochemical application. The sensitivity of CVD diamond layers to the electroactive species indicates on possibility of application of this material for construction of chemical and biological sensors. Originality/value: The characteristics of diamond electrodes and the resistivity of this material to the chemical attack indicate that it can be employed in a number of electrochemical applications and additionally it can work in harsh environment. The HF CVD diamond layer seems to be the new, promising and versatile material for electrochemical applications.

3

CVD diamond: from growth to application

Fabisiak K., Staryga E.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

264-269

EN

Purpose: The main purpose of these studies was to give a short review of basic diamonds properties and indicate possibilities of different applications of this material. As an example, the application of CVD (Chemical Vapour Deposition) diamond layer in electrochemistry was shown. Design/methodology/approach: The diamond layers were synthesized using Hot Filament CVD (HF CVD) technique from a mixture of methanol and hydrogen. The physical and electrochemical properties of the obtained layers were studied by Raman spectroscopy and Cyclic Voltammetry (CV). Findings: It was shown that it is possible to synthesize the diamond layers of different morphology and quality. Raman microprobe measurements showed that quality of diamond films deposited by HF CVD method reflect their morphology. CV measurements showed that the fabricated electrodes had wide potential window almost twice bigger in comparison to the classical Pt electrode. Research limitations/implications: The interaction of diamond layers with chemical and biological environment is not complete. Practical implications: CVD diamond (synthetic diamond made by a chemical vapour deposition process) is an important family of materials used in microelectronic and optoelectronic packaging and for laser and detector windows. Its ultra-high thermal conductivity enables to increase microprocessor frequency and output power of microelectronic and optoelectronic devices. Diamond is resistant to chemical attack and chemical sensors based on the fact it can work in harsh environment. Originality/value: The paper underlines an important role of diamond films as a promising material for production of electrodes for electrochemical applications.

4

Field emission and microstructural characterization of diamond films deposited by HF CVD method

Jarzyńska D., Staryga E., Znamirowski Z., Fabisiak K., Gotszalk T., Woszczyna M., Strzelecki W., Dłużniewski M.

Scientific Bulletin. Physics / Lodz University of Technology

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2007

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Vol. 28

13-26

EN

Electron emission from diamond films (DF) deposited using HF CVD technique on silicon substrates has been studied. The field emission characteristics were analyzed using the Fowler-Nordheim model. The diamond films were also characterized by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Raman Spectroscopy (RS) and Electron Spin Resonance (ESR) techniques. The correlation between electron field emission of investigated films, Raman spectra and concentration of paramagnetic centres has been discussed. The electron emission properties of diamond films improved after doping with nitrogen. The field emission was obtained at turn-on electric field equal to about 10 V/µm and about 3 V/µm, for undoped diamond films and N-doped diamond films, respectively. It seems that the change of turn-on field values and other emissive properties of thin diamond layers may be caused by different content of non-diamond phase (e.g. graphite phase) induced by doping.

PL

Przeprowadzono badania emisji polowej z warstw diamentowych osadzonych przy użyciu metody HF CVD na podłożach krzemowych typu n i p. Charakterystyki emisyjne analizowano na podstawie modelu Fowlera-Nordheima. Wytworzone warstwy scharakteryzowano przy użyciu następujących metod: SEM, AFM, spektroskopii Ramana i Elektronowego Rezonansu Spinowego (ESR). Przeprowadzono dyskusję wyników, wskazując na korelację pomiędzy wynikami emisji polowej a koncentracją centrów paramagnetycznych oraz widmami ramanowskimi badanych warstw diamentowych. Zaobserwowano znaczną poprawę właściwości emisyjnych heterostruktur, w których warstwa diamentowa domieszkowana została azotem. Dla układów z niedomieszkowanymi warstwami diamentowymi wartość natężenia pola włączeniowego wynosiła około 10 V/ µm, zaś dla domieszkowanych azotem warstw diamentowych wartość ta równa jest 3 V/µm. Różnice w wartościach pola włączeniowego dla odpowiednich układów wynikają prawdopodobnie z różnej zawartości materii grafito-podobnej w badanych warstwach diamentowych. Warstwy domieszkowane azotem są silnie zdefektowane i zawierają znaczną ilość materii grafitopodobnej.

5

Czy diament jest właściwym materiałem do wytworzenia emitera polowego?

Jarzyńska D., Staryga E., Znamirowski Z., Fabisiak K.

Elektronika : konstrukcje, technologie, zastosowania

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2007

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Vol. 48, nr 2

12-15

EN

Electron emission from diamond films (DF) deposited on silicon substrates has been studied. The DF's were synthesized using HF CVD technique. The electron field-emission properties were examined by measuring the field-emission current as a function of applied macroscopic electric field. The field emission characteristics were described using the Fowler-Nordheim model. The diamond films were also characterized by Scanning Electron Microscopy (SEM), Raman Spectroscopy (RS), and Electron Spin Resonance (ESR) techniques. Raman spectra of DF's exhibit spectral features with a well-defined peak at 1332 cm⁻¹, characteristic for diamond. The correlation between electron field emission of investigated films, Raman spectra and concentration of paramagnetic centers has been discussed. The electron emission properties of diamond films improved after doping by nitrogen. The field emission was obtained at turn-on electric field about 10 V/µm and about 4 V/µm, for undoped diamond films and N-doped diamond films respectively. It seems that the change of turn-on field values and emissive properties of thin diamond layers may be caused by different content of non-diamond phase (e.g. graphite phase) in diamond films.

6

Simple model for the thermal conductivity estimation on the basis of Raman and ESR spectroscopy measurements

Masierak W., Fabisiak K., Kaczmarski M., Kozanecki M.

Optica Applicata

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2006

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Vol. 36, nr 2-3

225-234

EN

The diamond films were grown at different working gas pressure in the range of 20-80 mbar by using hot filament chemical vapor deposition (HF CVD) technique. It was observed that the film morphology was dependent on deposition pressure and changed from so called "ball-like" via (111) and (100) type to the morphology of mixed character. The diamond film quality was studied by means of Raman and ESR (electron spin resonance) spectroscopy measurements. Within the presented work a simplified model for heat conductivity was proposed which allows to estimate the value of the thermal conductivity on the basis of Raman and ESR measurements. The obtained results are in good agreement with those reported in literature.

7

Emission properties of diamond and diamond-like carbon films deposited by various methods

Jarzyńska D., Staryga E.

Scientific Bulletin. Physics / Lodz University of Technology

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2005

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Vol. 25

15-34

EN

The electron field-emission properties of diamond-like carbon (DLC) thin films and diamond films (DF) were examined by measuring the field-emission current as a function of applied macroscopic electric field. The DLC and DF films were deposited on flat silicon substrates by means of RF PCVD and HF CVD techniques, respectively. The field emission research was carried out using a diode configuration. The results of field emission were analyzed using the Fowler - Nordheim model. The conditioning process of DF and DLC films as the effect improving the electron emission characteristics of these films was studied. The DF films showed better characteristics, that is, lower turn-on field, than DLC films. The characteristics of the investigated carbon-based films depended not only on the structure and sp2 inclusions but also on the film thickness and applied bias voltage.

PL

Właściwości emisyjne warstw diamentowych (DF) i diamentopodobnych (DLC) określono w wyniku pomiaru prądu emisji w funkcji przyłożonego makroskopowego pola elektrycznego. Warstwy węglowe osadzone zostały na gładkim podłożu krzemowym przy użyciu metody HF CVD i RF CVD, odpowiednio dla warstw DF i DLC. Charakterystyki emisyjne zmierzono przy użyciu techniki wykorzystującej sondę anodową, a uzyskane na ich podstawie wyniki analizowano w oparciu o model Fowlera-Nordheima. W pracy rozważa się wpływ różnorodnych czynników na właściwości emisyjne badanych układów warstwa węglowa/półprzewodnik. Przeprowadzono proces kondycjonowania warstw węglowych prowadzący do polepszenia właściwości emisyjnych badanych warstw. Dla warstw DLC wytwarzanych przy większych wartościach potencjału autopolaryzacji, uzyskano większe wartości prądu emisji. Morfologię warstw DF i DLC zbadano przy użyciu skaningowej mikroskopii elektronowej (SEM). Zastosowanie spektroskopii ramanowskiej umożliwiło określenie struktury warstw diamentowych i diamentopodobnych.

8

Structure of interfaces in heteroepitaxial diamond films.

Jager W., Wittorf D., Urban K.

Inżynieria Materiałowa

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1998

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R. XIX, nr 4

785-790

EN

High-resolution transmission electron microscopy (HRTEM) studies of diamond films grown on Si (100) substrates by microwave-assisted chemical vapour deposition show that, under optimized conditions, epitaxially oriented diamond grains may form directly on Si or on thin interlayers of nanocrystalline Beta-SiC. The orientation relationships between the crystal lattices can be described by a near-coincidence site lattice model if small elastic lattice distortions are taken into account. Characteristic of the structure of large-angle grain boundaries are facets parallel to the {111} planes of the diamond lattice. Lattice images of the {110}-diamond lattice planes in <001>-zone axes orientations depict that the structure of small-angle grain boundaries can be described by a dislocation model. Large open volumes and additional second carbon phases are not found at the grain boundaries in diamond films beyond 10 micrometers. Such microscopic investigations of the structure of interfaces in diamond films on silicon are essential for a fundamental understanding of the deposition process and of the correlation of structural with physical interface properties, such as e.g. thermal transport.