Influence of surface modifications on the electronic properties of CVD diamond films

Küttel

Journal of Vacuum Science &Amp; Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena

et al. 1999

Section: A Characterization By Raman and Photoelectron Spectroscopymentioning

confidence: 99%

Field emission properties of nanocrystalline chemically vapor deposited-diamond films

Küttel

Journal of Vacuum Science &Amp; Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena

et al. 1999

Applied Surface Science

“…Energy loss spectroscopy of photoelectrons emitted from the C1s core level has been used previously either for investigations of the role of surface hydrogen and oxygen atom coverage [11,12] as well as for the study of seeding and growth of nano-and microcrystalline diamond films [16][17][18][19]. For the assessment of the non diamond residual phase, the ratio of the bulk ( + ) plasmon loss of the diamond phase to the main C1s line (characteristic of the near-surface over typically 5 nm) was tentatively correlated to the ratio of G and D lines in Raman spectra (characteristic of a bulk depth >100 nm) [17].…”

Section: Introductionmentioning

confidence: 99%

“…XPS and UPS were used to study the partial hydrogen coverage and the variety of oxygen containing chemical functionalities in the as-grown state, after intentional surface hydrogenation and after liquid phase or gas phase oxidation [11][12][13][14]. Alternatively, High Resolution EELS has been used to follow changes in surface chemical bonds after hydrogenation or annealing steps [15].…”

Section: Introductionmentioning

confidence: 99%

Sensitivity of photoelectron energy loss spectroscopy to surface reconstruction of microcrystalline diamond films

David

Pinault-Thaury

Ballutaud

et al. 2013

International audienceIn X-ray Photoelectron Spectroscopy (XPS), binding energies and intensities of core level peaks are commonly used for chemical analysis of solid surfaces, after subtraction of a background signal. This background due to photoelectron energy losses to electronic excitations in the solid (surface and bulk plasmon excitation, inter band transitions) contains valuable information related to the near surface dielectric function ε(ħω). In this work, the sensitivity of Photoelectron Energy Loss Spectroscopy (PEELS) is investigated using a model system, namely the well-controlled surface reconstruction of diamond. Boron-doped microcrystalline thin films with a mixture of (1 1 1) and (1 0 0) preferential orientations were characterized in the as-grown state, with a partially hydrogenated surface, and after annealing at 1150 °C in ultra high vacuum. After annealing, the bulk (σ + π) plasmon of diamond at 34.5 eV is weakly attenuated but no evidence for surface graphitization is observed near 6 eV, as confirmed by electronic properties. Unexpected features which appear at 10 ± 1 eV and 19 ± 1 eV in the energy loss distribution are well described by simulation of surface plasmon excitations in graphite-like materials; alternatively, they also coincide with experimental inter band transition losses in some graphene layers. This comparative study shows that the PEELS technique gives a clear signature of weak effects in the diamond surface reconstruction, even in the absence of graphitization. It confirms the sensitivity of PEELS acquisition with standard XPS equipment as a complementary tool for surface analysis

“…The O-termination surface of a BDD presents high surface energy and positive electron affinity, 22,[24][25][26] thereby favoring hydroxyl radicals ( · OH) formation during anodic oxidation. 27 Thus, this feature has been widely used in oxidation degradation of organic pollutants in waste water.…”

mentioning

confidence: 99%

Investigation on Electrochemically Cathodic Polarization of Boron-Doped Diamond Electrodes and Its Influence on Lead Ions Analysis

Jiang

Liú

Jiang³

et al. 2014

J. Electrochem. Soc.

The purpose of this paper is to further understand the dependence of the electrochemical activity of a boron-doped diamond (BDD) film electrode on its surface boron doping concentration and the pretreatment applied to its surface. An electrochemically cathodic polarization (−3 V vs. SCE) with a varying polarization duration (5-50 min) was carried separately out to three types of BDDs with a boron doping level of 700, 2500, 8000 ppm in 0.5 M H 2 SO 4 solution. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to evaluate surface activity of the BDDs with and without cathodic polarizations by using 1.0 mM Fe(CN) 6 3−/4− . Moreover, the surface activity of the polarized BDD electrodes was examined further by using anodic stripping voltammetry to detect a series of known concentrations of Pb 2+ . Our results indicated that the applied cathodic polarization significantly improved the surface activity of the as-received BDD, and exhibited more active effect on the surface of a higher boron doping level BDD compared to a lower boron doping level BDD, thereby improving the ability of the polarized BDDs to detect trace Pb(II) in aqueous solutions by anodic stripping voltammetry. Boron-doped diamond (BDD) electrodes not only exhibit similar chemical-stability to that obtained in graphite and glassy carbon electrodes, but also possess a rather wide electrochemical window (>3 V) and very low background current. Thus, it can be a promising replacement for dropping mercury electrode and classic other electrodes used in electrochemical sensors, 1 electrochemical synthesis, 2 electrooxidization decomposition of pollutants, 3 and electroanalysis. BDD is characterized by p-type semiconductor 5-9 and its electrochemical property is dependent strongly on boron doping level, 10 purity of the diamond, crystal orientation of grain 11 and the kind of atom/group bonded chemically to carbon atoms on the surface of diamond. Generally, the electrochemical property of BDD electrodes is primarily determined by the terminal type of the carbon atoms on the surface. The surface termination of an as-deposited BDD electrode is H-termination, 9,12-15 but the H-terminal surface is also converted to a O-terminated surface as it is exposed to air, 8 or an aqueous solution containing strong oxidizers, or subjected to an electrochemically anodic treatment. [16][17][18][19][20] The change in surface carbon atom termination alters undoubtedly the kinetics of redox reactions occurring on the BDD surface due to a distinct difference in electronic structure and surface energy between H-terminated and O-terminated surface. [21][22][23] Therefore, in order to make full use of the merits of BDD electrodes, it is important to make the type of surface carbon termination of a BDD electrode match up with application purposes.The O-termination surface of a BDD presents high surface energy and positive electron affinity, 22,24-26 thereby favoring hydroxyl radicals ( · OH) formation during anodic oxidation.27 Thus, this feature has be...