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1

Thermoluminescence properties of undoped diamond films deposited using HF CVD technique

Paprocki K., Winiecki J., Kabacińska R., Przegiętka K., Szybowicz M., Fabisiak K.

Materials Science Poland

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2017

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Vol. 35, No. 4

785--790

EN

Natural diamond has been considered as a perspective material for clinical radiation dosimetry due to its tissue biocompatibility and chemical inertness. However, the use of natural diamond in radiation dosimetry has been halted by the high market price. The recent progress in the development of CVD techniques for diamond synthesis, offering the capability of growing high quality diamond layers, has renewed the interest in using this material in radiation dosimeters having small geometrical sizes. Polycrystalline CVD diamond films have been proposed as detectors and dosimeters of β and α radiation with prospective applications in high-energy photon dosimetry. In this work, we present a study on the TL properties of undoped diamond film samples grown by the hot filament CVD (HF CVD) method and exposed to β and α radiation. The glow curves for both types of radiation show similar character and can be decomposed into three components. The dominant TL peaks are centered at around 610 K and exhibit activation energy of the order of 0.90 eV.

2

Electrical properties and Mott parameters of polycrystalline diamond films synthesized by HF CVD method from hydrogen/methanol gas mixture

Banaszak-Piechowska A., Fabisiak K., Staryga E., Paprocki K.

Materials Science Poland

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2017

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Vol. 35, No. 4

830--837

EN

The influence of diamond crystallinity and preferred orientation on electronic conductivity of synthetic diamond films grown by hot filament chemical vapour deposition (HFCVD) was investigated. The CVD diamond films of different morphologies and crystallite sizes varying from 36 nm to 67 nm, measured in ‹2 2 0› direction were considered. The charge transport mechanism in the diamond samples was studied using temperature dependent DC conductivity measurements. The obtained results showed that in the temperature range of 90 K to 300 K charge transport is realized via Variable Range Hopping (VRH, m = 1/4) mechanism. Using VRH model, the Mott parameters were evaluated i.e. density of states at Fermi level N(EF) (0.22 × 1015 eV-1·cm-3 to 1.7 × 1015 eV-1·cm-3), hopping energy W (43.5 meV to 142.3 meV) and average hopping distance R (1.49 × 10-5cm to 2.56 × 10-5cm). It was shown that above mentioned parameters strongly depend on diamond film preferential orientation.

3

Chemically vapor deposited diamond films as dosimetric material for potential clinical applications

Kabacińska R., Winiecki J., Przegiętka K., Szybowicz M., Fabisiak K., Paprocki K.

Materials Science Poland

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2017

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Vol. 35, No. 4

702--706

EN

Thermally stimulated luminescence (TL), cathodoluminescence (CL) and Raman spectroscopy of CVD diamond films grown on silicon substrates have been studied in order to obtain information on defects created during the growth, which induce the levels within the gap. TL between 300 K and 700 K, and CL from 200 nm to 1200 nm have been teasured. The glow curves show a peak located around 610 K with different intensities, depending on the sample thickness, associated with a trap of energy, equal to 0.83 eV and with attempt-to-escape-time of the order of 108 s-1. Broad CL bands observed at 428±1 nm (2.90 ±0.01 eV) and 500±1 nm (2.47±0.004 eV) are attributed to closely spaced and widely separated donor-acceptor (D-A) pairs, respectively. The TL and CL results were correlated with diamond quality estimated from Raman spectroscopy measurements.

4

Effect of annealing temperature on optical and electrical properties of metallophthalocyanine thin films deposited on silicon substrate

Skonieczny R., Popielarski P., Bała W., Fabisiak K., Paprocki K., Jancelewicz M., Kowalska M., Szybowicz M.

Materials Science Poland

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2016

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Vol. 34, No. 3

676--683

EN

The cobalt phthalocyanine (CoPc) thin films (300 nm thick) deposited on n-type silicon substrate have been studied using micro-Raman spectroscopy, atomic force spectroscopy (AFM) and I-V measurement. The CoPc thin layers have been deposited at room temperature by the quasi-molecular beam evaporation technique. The micro-Raman spectra of CoPc thin films have been recorded in the spectral range of 1000 cm-1 to 1900 cm-1 using 488 nm excitation wavelength. Moreover, using surface Raman mapping it was possible to obtain information about polymorphic forms distribution (before and after annealing) of metallophthalocyanine (α and β form) from polarized Raman spectra. The I-V characteristics of the Au/CoPc/n-Si/Al Schottky barrier were also investigated. The obtained results showed that influence of the annealing process plays a crucial role in the ordering and electrical conductivity of the molecular structure of CoPc thin films deposited on n-type silicon substrate.

5

Badanie jakościowe materiałów węglowych za pomocą spektroskopii Ramana

Dychalska A., Paprocki K., Fabisiak K., Szybowicz M.

LAB Laboratoria, Aparatura, Badania

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2016

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R. 21, nr 5

6--7

PL

Praca ta prezentuje możliwość zastosowania spektroskopii Ramana do badań jakościowych materiałów węglowych typu DLC (diamond-like carbon). Badania zmiany parametrów spektralnych pasm charakterystycznych D i G w zakresie od temperatury pokojowej do 300°C umożliwiły obserwację wpływu procesu wygrzewania na przechodzenie materiału z formy węgla amorficznego do formy zbliżonej do nanokrystalicznego grafitu.

6

Temperature dependence of stress in CVD diamond films studied by Raman spectroscopy

Dychalska A., Fabisiak K., Paprocki K., Dudkowiak A., Szybowicz M.

Materials Science Poland

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2015

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Vol. 33, No. 3

620--626

EN

Evolution of residual stress and its components with increasing temperature in chemical vapor deposited (CVD) diamond films has a crucial impact on their high temperature applications. In this work we investigated temperature dependence of stress in CVD diamond film deposited on Si(100) substrate in the temperature range of 30 degrees C to 480 degrees C by Raman mapping measurement. Raman shift of the characteristic diamond band peaked at 1332 cm(-1) was studied to evaluate the residual stress distribution at the diamond surface. A new approach was applied to calculate thermal stress evolution with increasing temperature by using two commonly known equations. Comparison of the results obtained from the two methods was presented. The intrinsic stress component was calculated from the difference between average values of residual and thermal stress and then its temperature dependence was discussed.

7

Study of CVD diamond layers with amorphous carbon admixture by Raman scattering spectroscopy

Dychalska A., Popielarski P., Franków W., Fabisiak K., Paprocki K., Szybowicz M.

Materials Science Poland

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2015

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Vol. 33, No. 4

799--805

EN

Raman spectroscopy is a most often used standard technique for characterization of different carbon materials. In this work we present the Raman spectra of polycrystalline diamond layers of different quality, synthesized by Hot Filament Chemical Vapor Deposition method (HF CVD). We show how to use Raman spectroscopy for the analysis of the Raman bands to determine the structure of diamond films as well as the structure of amorphous carbon admixture. Raman spectroscopy has become an important technique for the analysis of CVD diamond films. The first-order diamond Raman peak at ca. 1332 cm−1 is an unambiguous evidence for the presence of diamond phase in the deposited layer. However, the existence of non-diamond carbon components in a CVD diamond layer produces several overlapping peaks in the same wavenumber region as the first order diamond peak. The intensities, wavenumber, full width at half maximum (FWHM) of these bands are dependent on quality of diamond layer which is dependent on the deposition conditions. The aim of the present work is to relate the features of diamond Raman spectra to the features of Raman spectra of non-diamond phase admixture and occurrence of other carbon structures in the obtained diamond thin films.

8

Wpływ morfologii warstwy na jakość elektrochemiczną elektrody diamentowej

Kowalska M., Fabisiak K., Wrzyszczyński A.

Przemysł Chemiczny

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2014

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T. 93, nr 10

1712-1715

PL

Elektrody diamentowe o różnej morfologii powierzchni i różnych właściwościach fizycznych zostały wyprodukowane metodą chemicznego osadzania z fazy gazowej (HFCVD). Jedynym parametrem, który zmieniano podczas syntezy była zawartość metanolu w gazie roboczym. Ocenę jakości diamentu i identyfikację innych niż diamentowa faz węgla w wytworzonych warstwach prowadzono za pomocą spektroskopii Ramana. Właściwości elektrochemiczne otrzymanych elektrod badano przy użyciu woltamperometrii cyklicznej (CV), stosując podstawowe pary redoks [Fe(CN)₆]⁴⁻/³⁻ w 0,1 M Kcl. Metoda CV pozwoliła również określić wpływ jakości diamentu, morfologii powierzchni oraz zawartości fazy węgla amorficznego na kinetykę reakcji elektrochemicznych zachodzących na powierzchni elektrod diamentowych oraz określić ich czułość. Zbadano parametry kinetyczne reakcji, takie jak stała szybkości reakcji oraz współczynnik przenoszenia ładunku (elektronu). Uzyskane wyniki wskazują, że analityczna wydajność niedomieszkowanych elektrod diamentowych może być kontrolowana poprzez zmianę zawartości węglowodoru w gazie roboczym, mającą wpływ na zawartość fazy węgla amorficznego w uzyskanych elektrodach diamentowych. Prowadzone badania miały na celu poznanie procesów zachodzących na powierzchni diamentu, a w szczególności jego oddziaływania z elektrolitem, co ma duże znaczenie w zastosowaniu elektrod diamentowych jako sensorów chemicznych, jak również elektrod stosowanych do utleniania zanieczyszczeń organicznych.

EN

W substrate was covered with thin diamond layer by hotfilament chem. vapor deposition from MeOH/H₂ mixt. At 1100 K. Three electrodes were studied for electrochem. behavior by cyclic voltammetry and for phys. properties by electron microscopy and Raman spectroscopy.

9

CVD diamond layers for electrochemistry

Kowalska M., Fabisiak K., Wrzyszczyński A., Banaszak A., Szybowicz M., Paprocki K., Bała W, Bylicki F

Materials Science Poland

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2014

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Vol. 32, No. 3

475--480

EN

Diamond electrodes of different morphologies and qualities were manufactured by hot filament chemical deposition (HF CVD) techniques by changing the parameters of diamond growth process. The estimation of diamond quality and identification of different carbon phases was performed by Raman spectroscopy measurements. The effect of diamond quality and amorphous carbon phase content on the electrochemical response of an obtained diamond electrode in 0.5 M H2SO4 as supporting electrolyte was investigated by cyclic voltammetry with [Fe(CN)6]4−/3− as a redox probe. The kinetic parameters such as catalytic reaction rate constant k0 and electron transfer coefficient α were determined. The obtained results show that the analytical performance of undoped diamond electrodes can be implemented just by the change of diamond layers quality.

10

Diament jako materiał przetwornikowy do produkcji biosensorów

Mosińska L., Fabisiak K., Paprocki K., Kowalska M., Popielarski P., Szybowicz M., Stasiak A.

Przemysł Chemiczny

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2013

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T. 92, nr 6

919--923

11

Cyclic voltammetry and impedance studies of undoped diamond films

Mosińska L., Kowalska M., Popielarski P., Fabisiak K., Paprocki K., Szybowicz M., Wrzyszczynski A., Zhusupkalieva G. K.

Materials Science Poland

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2013

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Vol. 31, No. 1

146-150

EN

The undoped, polycrystalline diamond films were deposited on tungsten wire substrates by hot filament chemical vapor deposition (HF CVD), using a precursor gas mixture of methanol with excess of hydrogen. The morphology and quality of the as-deposited films were monitored by scanning electron microscopy (SEM) and Raman spectroscopy. The surface morphology analyzed by SEM resembles a continuous and well faceted diamond film. Raman results showed essential differences in qualities of diamond films grown at different hydrocarbon concentrations. The electrochemical properties of diamond electrodes were examined with cyclic voltammetry (CV) and the electrochemical impedance spectroscopy (EIS). The CV experiments revealed a large chemical window (>~4.3 V) of undoped diamond. Analysis of the ferrocyanide-ferricyanide couple at a diamond electrode suggests some extent of electrochemical quasi-reversibility, but the rates of charge transfer across the diamond substrate interface vary with diamond quality.

12

Zastosowanie warstw diamentowych w woltamperometrii cyklicznej

Kowalska M., Fabisiak K., Wrzyszczyński A.

Przemysł Chemiczny

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2012

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T. 91, nr 11

2146--2149

PL

Zbadano możliwości zastosowania warstw diamentowych otrzymywanych z fazy gazowej do zastosowań elektrochemicznych. Warstwy diamentowe o różnych właściwościach fizycznych otrzymywano przy użyciu reaktora HF CVD (hot-filament chemical vapor deposition) sterując odpowiednio parametrami syntezy. Otrzymane warstwy charakteryzowane były m.in. za pomocą spektroskopii Ramana, skanningowej mikroskopii elektronowej (SEM) oraz dyfrakcji promieni X (XRD). W zależności od warunków syntezy warstwy różniły się morfologią, wielkością krystalitów oraz zawartością fazy węgla amorficznego. Właściwości te miały istotny wpływ na właściwości elektrochemiczne elektrod diamentowych, które badano za pomocą woltamperometrii cyklicznej (CV).

EN

Polycryst. diamond layers (1,5–10 µA thick) were deposited on a W wire by hot-filament decompn. of MeOH vapours in H₂ at 1000 K and 50 mbar and studied for morphology by SEM, Raman spectroscopy and voltammetry. The diamond layers showed a high quality.

13

Electron emission from nitrogen-doped polycrystalline diamond/Si heterostructures

Staryga E., Fabisiak K., Dłużniewski M., Bąk G.

Materials Science Poland

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2012

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Vol. 30, No. 4

390--397

EN

The field electron emission from polycrystalline diamond/silicon and nitrogen-doped polycrystalline diamond/silicon structures obtained by HF CVD deposition method has been investigated. Electron emission currents from the samples were measured in a chamber at the pressure equal to 2ź106 Pa in sphere-to-plane diode configuration with the 5 žm distance between electrodes. As expected, the results confirm the relation between the structure of diamond films and their emission properties. The type of silicon substrate also infiuences the value of emission currents and the diamond/n-Si heterostructures exhibit better electron emission than diamond/p-Si ones. The nitrogen doping significantly enhances the electron emission from the heterostructures and their emission parameters. The values of the threshold field between 2 V/žm and 3 V/žm were registered, the values of emission current close to 1 mA/cm2at 5 V/žm for the nitrogen-doped films were obtained. The shape of current-voltage characteristics for nitrogen-doped polycrystalline films may be interpreted in terms of stochastic distribution of diameters of conducting channels which form the emission centers.

14

Wpływ struktury warstwy diamentowej na emisję elektronów z układu powłoka diamentowa/krzem

Staryga E., Fabisiak K., Dłużniewski M., Znamirowski Z.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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Vol. 52, nr 8

21-23

PL

Zbadano prądy emisji dla układów polikrystaliczna warstwa diamentowa/ krzem i domieszkowana polikrystaliczna warstwa diamentowa/krzem. Wyniki potwierdzają istnienie relacji pomiędzy strukturą warstw diamentowych i ich właściwościami emisyjnymi. Domieszka azotu wpływa na wzrost prądu emisji z badanych układów. Kształt charakterystyk prądowo-polowych dla domieszkowanych azotem warstw diamentowych może być interpretowany przy założeniu stochastycznego rozkładu rozmiaru promieni przewodzących kanałów, które tworzą centra emisji.

EN

The emission currents from polycrystalline diamond/silicon and nitrogen-doped polycrystalline diamond/silicon structures have been investigated. As expected, the results confirm the relation between the structure of diamond films and their emission properties. The nitrogen doping enhances significantly the electron emission from the heterostructures. The shape of current-voltage characteristics for nitrogen-doped polycrystalline films may be interpreted in terms of stochastic distribution of radius of conducting channels which form the emission centers.

15

Electron paramagnetic resonance and scanning electron microscopy characterization of diamond films fabricated by HF CVD method

Fabisiak K., Szreiber M., Uniszkiewicz C., Runka T., Kasprowicz D.

Optica Applicata

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2009

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Vol. 39, nr 4

833-837

EN

Defects in diamond films, produced by the hot filament chemical vapour deposition (HF CVD) of methanol and hydrogen mixture as function of gas composition, were investigated by electron paramagnetic resonance (EPR), scanning electron microscopy (SEM) and Raman spectroscopy measurements. We found an isotropic g-value (2.003š0.0002) independent of growth conditions. The peak-to-peak of EPR line width changes from 0.3 to 0.6 mT and the spin density increases from 2.3ź1017 to 3.2ź1018 spin/cm-3 with increasing concentration of methanol vapour. The EPR line in general shows double character and was found to be superposition of two components, a narrower Lorentzian and a broader Gaussian, suggesting the existence of two different types of defects in diamond layer. EPR measurements were supported by SEM observation.

16

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.

17

Wpływ domieszkowania azotem warstw diamentowych na właściwości emisyjne układu DF/Si

Staryga E., Znamirowski Z., Fabisiak K.

Elektronika : konstrukcje, technologie, zastosowania

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2009

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Vol. 50, nr 1

117-119

PL

Zbadano emisję elektronów z heterostruktur warstwa diamentowa/krzem i warstwa diamentowa domieszkowana azotem/krzem. Analiza natężenia prądu emisji w zależności od natężenia pola elektrycznego umożliwiła wyznaczenie parametrów emisyjnych (efektywna praca wyjścia, natężenie pola włączeniowego) wytworzonych heterostruktur. Badane układy odznaczały się stabilną pracą podczas pomiaru emisji polowej. Zaobserwowano znaczny wzrost prądu emisji w układach z domieszkowaną azotem warstwą diamentową w stosunku do prądu emisji z układów z niedomieszkowaną warstwą. Wyniki badań pokazują, iż wytworzone warstwy diamentowe, przy doborze odpowiednich parametrów procesu HF CVD, zastosowaniu domieszkowania azotem oraz wyborze odpowiedniego podłoża półprzewodnikowego, mogą stanowić dobry materiał na pokrycie emiterów polowych.

EN

The emission current from diamond/silicon and nitrogen doped diamond/silicon heterostructures has been investigated. The analysis of the emission current vs. electric field characteristics have enabled to determine the basic emission parameters (such as effective work function, turn-on field). The studied heterostructures was stable during the measurements. The nitrogen doping turned out to enhance the electron emission from the heterostructures significantly. The results presented prove that it is possible to obtain good electron emitters using silicon covered with polycrystalline diamond films provided that the properly chosen parameters of HF CVD preparation, including nitrogen doping, are used.

18

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.

19

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.

20

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.