The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform

Francisco Zaera - One of the best experts on this subject based on the ideXlab platform.

  • Activation of Metal-Organic Precursors by Electron Bombardment in the Gas Phase for Enhanced Deposition of Solid Films.
    The journal of physical chemistry letters, 2012
    Co-Authors: Huaxing Sun, Xiangdong Qin, Francisco Zaera
    Abstract:

    The incorporation of gas-phase electron-impact ionization and activation of metal-organic compounds into atomic layer deposition (ALD) processes is reported as a way to enhance film growth with stable precursors. Specifically, it is shown here that gas-phase activation of Methylcyclopentadienylmanganese Tricarbonyl, MeCpMn(CO)3, which was accomplished by using a typical nude ion gauge employed in many ultrahigh-vacuum (UHV) studies, enhances its dissociative adsorption on silicon surfaces, affording the design of ALD cycles with more extensive Mn deposition and at lower temperatures. Significantly higher Mn uptakes were demonstrated by X-ray photoelectron spectroscopy (XPS) on both silicon dioxide films and on Si(100) wafers Ar(+)-sputtered to remove their native oxide layer. The effectiveness of this electron-impact activation approach in ALD is explained in terms of the cracking patterns seen in mass spectrometry for the metal-organic precursor used.

  • Chemical Nature of the Thin Films that Form on SiO2/Si(100) Surfaces Upon Manganese Deposition
    The Journal of Physical Chemistry Letters, 2011
    Co-Authors: Huaxing Sun, Xiangdong Qin, Francisco Zaera
    Abstract:

    There has been much interest in recent years in the use of manganese for the self-formation of diffusion barriers to prevent the electromigration of copper interconnects into the underlying silicon substrate during microelectronic fabrication. However, the films resulting from the deposition of manganese on silicon wafers, which are covered by a thin native silicon dioxide layer, are complex and have not been fully characterized to date. Here we report on X-ray photoelectron spectroscopy (XPS) studies on the nature of films prepared by chemical means using Methylcyclopentadienylmanganese Tricarbonyl as the precursor. It was found that at the temperatures typically used for deposition, between approximately 550 and 750 K, a manganese silicate layer grows first upon reaction with the top SiO2 surface, and a thin manganese silicide film develops latter at the SiO2/Si(100) interface. The performance of these structures, of the silicide in particular, in microelectronic applications is still to be determined.

Y. K. Chau - One of the best experts on this subject based on the ideXlab platform.

  • Determination of Methylcyclopentadienylmanganese Tricarbonyl (MMT) in aqueous samples by SPME-GC-AED
    The Analyst, 1999
    Co-Authors: Fan Yang, Y. K. Chau
    Abstract:

    Solid phase microextraction (SPME) was successfuly applied to the determination of the gasoline additive Methylcyclopentadienylmanganese Tricarbonyl (MMT) in aqueous samples. The procedure is simple, efficient and solvent free. Ultra-trace levels of MMT (pg l–1) in water can be determined with the combination of SPME and gas chromatography–plasma atomic emission detection. The linear range is between 1 and 1000 pg l–1 with relative detection limits of 0.3 pg l–1 (as Mn) of MMT in water. The precision for replicate analyses (n = 4) of an MMT solution (10 pg l–1 as Mn) was 7.1% (RSD). Different kinds of aqueous samples were collected and extracted for the determination of MMT with the SPME technique. In spite of its short half-life in the presence of light, MMT was found in all highway runoff and sewage samples. The liquid–liquid extraction method was also used for MMT determination in highway runoff and lake water samples and the results from the two techniques were comparable.

  • Determination of Methylcyclopentadienylmanganese Tricarbonyl (MMT) in gasoline and environmental samples by gas chromatography with helium microwave plasma atomic emission detection
    Applied Organometallic Chemistry, 1997
    Co-Authors: Y. K. Chau, Fan Yang, Marion Brown
    Abstract:

    A highly sensitive and specific method is described for the determination of methyl-cyclopentadienylmanganese Tricarbonyl (MMT) in gasoline and environmental samples by gas chromatography-plasma atomic emission detection (GC-AED). The procedure is simple, rapid and free from interferences. The absolute limit of detection is 0.5 fg of MMT (0.5 x 10 -15 g) expressed as Mn. The precision for replicate injections (n=5) of an MMT solution (10 pg Mn) was 2.8% relative standard deviation (RSD). Applications of the method to analysis of gasoline (petrol), and preliminary results of the analyses of environmental samples such as air and roadside dirt, are given.

Huaxing Sun - One of the best experts on this subject based on the ideXlab platform.

  • Activation of Metal-Organic Precursors by Electron Bombardment in the Gas Phase for Enhanced Deposition of Solid Films.
    The journal of physical chemistry letters, 2012
    Co-Authors: Huaxing Sun, Xiangdong Qin, Francisco Zaera
    Abstract:

    The incorporation of gas-phase electron-impact ionization and activation of metal-organic compounds into atomic layer deposition (ALD) processes is reported as a way to enhance film growth with stable precursors. Specifically, it is shown here that gas-phase activation of Methylcyclopentadienylmanganese Tricarbonyl, MeCpMn(CO)3, which was accomplished by using a typical nude ion gauge employed in many ultrahigh-vacuum (UHV) studies, enhances its dissociative adsorption on silicon surfaces, affording the design of ALD cycles with more extensive Mn deposition and at lower temperatures. Significantly higher Mn uptakes were demonstrated by X-ray photoelectron spectroscopy (XPS) on both silicon dioxide films and on Si(100) wafers Ar(+)-sputtered to remove their native oxide layer. The effectiveness of this electron-impact activation approach in ALD is explained in terms of the cracking patterns seen in mass spectrometry for the metal-organic precursor used.

  • Chemical Nature of the Thin Films that Form on SiO2/Si(100) Surfaces Upon Manganese Deposition
    The Journal of Physical Chemistry Letters, 2011
    Co-Authors: Huaxing Sun, Xiangdong Qin, Francisco Zaera
    Abstract:

    There has been much interest in recent years in the use of manganese for the self-formation of diffusion barriers to prevent the electromigration of copper interconnects into the underlying silicon substrate during microelectronic fabrication. However, the films resulting from the deposition of manganese on silicon wafers, which are covered by a thin native silicon dioxide layer, are complex and have not been fully characterized to date. Here we report on X-ray photoelectron spectroscopy (XPS) studies on the nature of films prepared by chemical means using Methylcyclopentadienylmanganese Tricarbonyl as the precursor. It was found that at the temperatures typically used for deposition, between approximately 550 and 750 K, a manganese silicate layer grows first upon reaction with the top SiO2 surface, and a thin manganese silicide film develops latter at the SiO2/Si(100) interface. The performance of these structures, of the silicide in particular, in microelectronic applications is still to be determined.

Fan Yang - One of the best experts on this subject based on the ideXlab platform.

  • Determination of Methylcyclopentadienylmanganese Tricarbonyl (MMT) in aqueous samples by SPME-GC-AED
    The Analyst, 1999
    Co-Authors: Fan Yang, Y. K. Chau
    Abstract:

    Solid phase microextraction (SPME) was successfuly applied to the determination of the gasoline additive Methylcyclopentadienylmanganese Tricarbonyl (MMT) in aqueous samples. The procedure is simple, efficient and solvent free. Ultra-trace levels of MMT (pg l–1) in water can be determined with the combination of SPME and gas chromatography–plasma atomic emission detection. The linear range is between 1 and 1000 pg l–1 with relative detection limits of 0.3 pg l–1 (as Mn) of MMT in water. The precision for replicate analyses (n = 4) of an MMT solution (10 pg l–1 as Mn) was 7.1% (RSD). Different kinds of aqueous samples were collected and extracted for the determination of MMT with the SPME technique. In spite of its short half-life in the presence of light, MMT was found in all highway runoff and sewage samples. The liquid–liquid extraction method was also used for MMT determination in highway runoff and lake water samples and the results from the two techniques were comparable.

  • Determination of Methylcyclopentadienylmanganese Tricarbonyl (MMT) in gasoline and environmental samples by gas chromatography with helium microwave plasma atomic emission detection
    Applied Organometallic Chemistry, 1997
    Co-Authors: Y. K. Chau, Fan Yang, Marion Brown
    Abstract:

    A highly sensitive and specific method is described for the determination of methyl-cyclopentadienylmanganese Tricarbonyl (MMT) in gasoline and environmental samples by gas chromatography-plasma atomic emission detection (GC-AED). The procedure is simple, rapid and free from interferences. The absolute limit of detection is 0.5 fg of MMT (0.5 x 10 -15 g) expressed as Mn. The precision for replicate injections (n=5) of an MMT solution (10 pg Mn) was 2.8% relative standard deviation (RSD). Applications of the method to analysis of gasoline (petrol), and preliminary results of the analyses of environmental samples such as air and roadside dirt, are given.

Marion Brown - One of the best experts on this subject based on the ideXlab platform.