The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform

Hikaru Kobayashi - One of the best experts on this subject based on the ideXlab platform.

  • Ultrathin Sio2 Layer with a low leakage current density formed with ∼ 100% nitric acid vapor
    Nanotechnology, 2010
    Co-Authors: Woo-byoung Kim, Taketoshi Matsumoto, Hikaru Kobayashi
    Abstract:

    An ultrathin silicon dioxide (Sio2) Layer with 0.65?1.5?nm thickness has been formed by ~ 100% nitric acid (HNO3) vapor oxidation, and its electrical characteristics and physical properties are investigated. The oxidation kinetics follows a parabolic law except for the ultrathin (?0.8?nm) region, indicating that diffusion of oxidizing species (i.e.?oxygen atoms generated by decomposition of ~ 100%?HNO3 vapor) through a growing Sio2 Layer is the rate-determining step. The diffusion activation energy for HNO3 vapor oxidation is 0.14?eV, much lower than that of thermal oxidation of 1.24?eV. The leakage current density for the 0.65?nm Sio2 Layer formed by HNO3 vapor oxidation is lower by approximately one order of magnitude than that for a thermal oxide Layer with the same thickness. The low leakage current density is attributed to (i) the atomically flat Sio2/Si interface and uniform thickness of the ultrathin Sio2 Layer, (ii) the low concentration of suboxide species and the low interface state density and (iii) the high atomic density of the Sio2 Layer, which leads to a high band discontinuity energy at the Sio2/Si interface. The leakage current density is further decreased by PMA at 250??C in 5?vol% H2 atmosphere.

  • Ultrathin Sio2 Layer with an extremely low leakage current density formed in high concentration nitric acid
    Journal of Applied Physics, 2009
    Co-Authors: Woo-byoung Kim, Taketoshi Matsumoto, Hikaru Kobayashi
    Abstract:

    An ultrathin silicon dioxide (Sio2) Layer of 1.2–1.4 nm thickness has been formed by immersion of Si wafers in nitric acid (HNO3) aqueous solutions, and its electrical characteristics and physical properties are investigated as a function of the HNO3 concentration. Measurements of transverse optical and longitudinal optical phonons of Si–O–Si asymmetric stretching vibrational mode for Sio2 indicate that the atomic density of the Sio2 Layer increases with the HNO3 concentration. X-ray photoelectron spectroscopy measurements show that the valence band discontinuity energy at the Sio2/Si interface also increases and the concentration of suboxide species decreases with the HNO3 concentration. The leakage current density of the ⟨Al/Sio2/Si(100)⟩ metal-oxide-semiconductor (MOS) diodes with the Sio2 Layer formed in HNO3 aqueous solutions decreases with the HNO3 concentration and also decreases by postmetallization annealing (PMA) treatment at 250 °C in 5 vol % hydrogen atmosphere. For the MOS diodes with the SiO...

  • Effects of postmetallization annealing on ultrathin Sio2 Layer properties
    Applied Physics Letters, 2002
    Co-Authors: Asuha, Toshiro Yuasa, Osamu Maida, Hikaru Kobayashi
    Abstract:

    Observation of both longitudinal optical and transverse optical phonons of ∼1.3 nm ultrathin silicon dioxide (Sio2) Layers formed by immersion in nitric acid shows that the Sio2 density increases by 16% after postoxidation annealing (POA) at 900 °C. For the Sio2 Layers without POA, postmetalization annealing (PMA) greatly decreases the Sio2 thickness from 1.3 to 0.2 nm, the effect of which is attributable to the reaction of aluminum with Sio2 to form a metallic mixture of aluminum oxide and Si. For Sio2 Layers with POA, PMA decreases the Sio2 thickness to a lesser extent (from 1.4 to 0.9 nm), because of the suppression of aluminum diffusion into Sio2 due to its dense structure. PMA is found to decrease the interface state density but increase the leakage current density.

C. Dumas - One of the best experts on this subject based on the ideXlab platform.

  • KFM detection of charges injected by AFM into a thin Sio2 Layer containing Si nanocrystals
    Microelectronic Engineering, 2008
    Co-Authors: C. Dumas, Laurence Ressier, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, P. Normand
    Abstract:

    Charge retention of Si nanocrystals elaborated by ultra-low energy ion implantation and thermal annealings into a thin Sio2 Layer is characterized by atomic force microscopy (AFM) and Kelvin force microscopy (KFM). Electrons and holes are injected under ambient conditions by applying different bias to a conductive AFM tip in contact with the grounded sample. A surface potential mapping of the sample by KFM is continuously carried out after charge injection. The temporal decay of injected charges and their corresponding lateral spreading are quantified. The results show that the presence of Si nanocrystals leads to a strong charge confinement.

  • Silicon nanoparticles synthesized in Sio2 pockets by stencil-masked low energy ion implantation and thermal annealing
    Superlattices and Microstructures, 2008
    Co-Authors: Jérémie Grisolia, C. Dumas, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Caroline Bonafos, M. A. F. Boogaart, J. Brugger, P. Normand
    Abstract:

    We propose an original approach called a “stencil-masked ion implantation process” for performing a spatially localized synthesis of a limited number of Si nanocrystals within a thin Sio2 Layer. In this process, the Sio2 Layer is irradiated with 1 keV silicon ions through a stencil mask containing apertures (from 100 nm to 2 μm), and subsequently thermally annealed to create Si nanocrystals. Scanning electron microscopy images show that the implanted areas mimic the mask geometry. Energy-filtered transmission electron microscopy and photoluminescence spectroscopy studies confirm that only the implanted areas are Si nanocrystal rich and light emitting. The smaller nanocrystal size detected near the edges of the implanted areas is attributed to dose reduction effects. This feature leads to a blueshift of the PL energy. Electrical properties of the structures produced are investigated using Al gate MOS capacitors. Room temperature and characteristics exhibit discrete current peaks that are associated with single-electron charging of the nanocrystals and electrostatic interaction of the trapped charges with the tunnelling current.

  • Photoluminescence spectroscopy and transport electrical measurements reveal the quantized features of Si nanocrystals embedded in an ultra thin Sio2 Layer
    physica status solidi (c), 2007
    Co-Authors: C. Dumas, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Marzia Carrada, Caroline Bonafos, Alain Claverie
    Abstract:

    In this paper, we have investigated the quantized charging features revealed by nanometer scale devices containing a 2D array of Si nanoparticles (nps) embedded into a Sio2 Layer. The Si nps were synthesized by ultra low energy ion implantation and annealing under slightly oxidizing ambient. The structural characteristics of the material (oxide thicknesses, nps size and density) have been studied by Transmission Electron Microscopy (TEM) and Energy Filtered TEM (EFTEM). Moreover, photoluminescence (PL) spectroscopy and electrical I(V) measurements using a MOS capacitor addressing only a few nps have been performed at room temperature. It is observed that, as the oxidizing annealing temperature increases, the nps size decreases and the oxide quality is restored. These features appear on the PL spectra as a blue shift of the PL red band linked to quantum confinement into nps and on the I(V) characteristics as an increase of the voltage peak width and a decrease of the main current background.

  • Influence of the thickness of the tunnel Layer on the charging characteristics of Si nanocrystals embedded in an ultra-thin Sio2 Layer
    Physica E: Low-dimensional Systems and Nanostructures, 2007
    Co-Authors: C. Dumas, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Marzia Carrada, Caroline Bonafos, Alain Claverie, M. Shalchian
    Abstract:

    In this paper, we have studied the effect of the thickness of the initial Sio2 Layer (5–7 nm) on the charge and discharge properties of a 2D array of Si nanoparticles embedded in these Sio2 Layers fabricated by ultra-low-energy ion implantation (ULE-II) and annealing. The structural characteristics of these nanocrystal-based memories (position of the nanocrystals with respect to the electrodes, size and surface density of the particles in the plane) were studied by transmission electron microscopy (TEM) and energy filtered TEM (EF-TEM). Electrical characterizations were performed at room temperature using a nano-MOS capacitor to be able to address only a few nanoparticles (nps). EFTEM gives the measurements of oxide thickness, injection, control and nps distances, size and density. I–V and I–t measurements exhibit current peaks and random telegraph signal fluctuations that can be interpreted as due to quantized charging of the nps and to some electrostatic interactions between the trapped charges and the tunnelling current. We have shown that these characteristics strongly vary with the initial oxide thickness, exhibiting several charging/discharging events for the 7-nm-thick Layer while charging events prevail in the case of 5-nm-thick Layer. These results indicate that the probability of discharging phenomena is reduced when the tunnel Layer thickness decreases.

Jérémie Grisolia - One of the best experts on this subject based on the ideXlab platform.

  • KFM detection of charges injected by AFM into a thin Sio2 Layer containing Si nanocrystals
    Microelectronic Engineering, 2008
    Co-Authors: C. Dumas, Laurence Ressier, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, P. Normand
    Abstract:

    Charge retention of Si nanocrystals elaborated by ultra-low energy ion implantation and thermal annealings into a thin Sio2 Layer is characterized by atomic force microscopy (AFM) and Kelvin force microscopy (KFM). Electrons and holes are injected under ambient conditions by applying different bias to a conductive AFM tip in contact with the grounded sample. A surface potential mapping of the sample by KFM is continuously carried out after charge injection. The temporal decay of injected charges and their corresponding lateral spreading are quantified. The results show that the presence of Si nanocrystals leads to a strong charge confinement.

  • Silicon nanoparticles synthesized in Sio2 pockets by stencil-masked low energy ion implantation and thermal annealing
    Superlattices and Microstructures, 2008
    Co-Authors: Jérémie Grisolia, C. Dumas, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Caroline Bonafos, M. A. F. Boogaart, J. Brugger, P. Normand
    Abstract:

    We propose an original approach called a “stencil-masked ion implantation process” for performing a spatially localized synthesis of a limited number of Si nanocrystals within a thin Sio2 Layer. In this process, the Sio2 Layer is irradiated with 1 keV silicon ions through a stencil mask containing apertures (from 100 nm to 2 μm), and subsequently thermally annealed to create Si nanocrystals. Scanning electron microscopy images show that the implanted areas mimic the mask geometry. Energy-filtered transmission electron microscopy and photoluminescence spectroscopy studies confirm that only the implanted areas are Si nanocrystal rich and light emitting. The smaller nanocrystal size detected near the edges of the implanted areas is attributed to dose reduction effects. This feature leads to a blueshift of the PL energy. Electrical properties of the structures produced are investigated using Al gate MOS capacitors. Room temperature and characteristics exhibit discrete current peaks that are associated with single-electron charging of the nanocrystals and electrostatic interaction of the trapped charges with the tunnelling current.

  • Photoluminescence spectroscopy and transport electrical measurements reveal the quantized features of Si nanocrystals embedded in an ultra thin Sio2 Layer
    physica status solidi (c), 2007
    Co-Authors: C. Dumas, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Marzia Carrada, Caroline Bonafos, Alain Claverie
    Abstract:

    In this paper, we have investigated the quantized charging features revealed by nanometer scale devices containing a 2D array of Si nanoparticles (nps) embedded into a Sio2 Layer. The Si nps were synthesized by ultra low energy ion implantation and annealing under slightly oxidizing ambient. The structural characteristics of the material (oxide thicknesses, nps size and density) have been studied by Transmission Electron Microscopy (TEM) and Energy Filtered TEM (EFTEM). Moreover, photoluminescence (PL) spectroscopy and electrical I(V) measurements using a MOS capacitor addressing only a few nps have been performed at room temperature. It is observed that, as the oxidizing annealing temperature increases, the nps size decreases and the oxide quality is restored. These features appear on the PL spectra as a blue shift of the PL red band linked to quantum confinement into nps and on the I(V) characteristics as an increase of the voltage peak width and a decrease of the main current background.

  • Influence of the thickness of the tunnel Layer on the charging characteristics of Si nanocrystals embedded in an ultra-thin Sio2 Layer
    Physica E: Low-dimensional Systems and Nanostructures, 2007
    Co-Authors: C. Dumas, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Marzia Carrada, Caroline Bonafos, Alain Claverie, M. Shalchian
    Abstract:

    In this paper, we have studied the effect of the thickness of the initial Sio2 Layer (5–7 nm) on the charge and discharge properties of a 2D array of Si nanoparticles embedded in these Sio2 Layers fabricated by ultra-low-energy ion implantation (ULE-II) and annealing. The structural characteristics of these nanocrystal-based memories (position of the nanocrystals with respect to the electrodes, size and surface density of the particles in the plane) were studied by transmission electron microscopy (TEM) and energy filtered TEM (EF-TEM). Electrical characterizations were performed at room temperature using a nano-MOS capacitor to be able to address only a few nanoparticles (nps). EFTEM gives the measurements of oxide thickness, injection, control and nps distances, size and density. I–V and I–t measurements exhibit current peaks and random telegraph signal fluctuations that can be interpreted as due to quantized charging of the nps and to some electrostatic interactions between the trapped charges and the tunnelling current. We have shown that these characteristics strongly vary with the initial oxide thickness, exhibiting several charging/discharging events for the 7-nm-thick Layer while charging events prevail in the case of 5-nm-thick Layer. These results indicate that the probability of discharging phenomena is reduced when the tunnel Layer thickness decreases.

Arnaud Arbouet - One of the best experts on this subject based on the ideXlab platform.

  • KFM detection of charges injected by AFM into a thin Sio2 Layer containing Si nanocrystals
    Microelectronic Engineering, 2008
    Co-Authors: C. Dumas, Laurence Ressier, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, P. Normand
    Abstract:

    Charge retention of Si nanocrystals elaborated by ultra-low energy ion implantation and thermal annealings into a thin Sio2 Layer is characterized by atomic force microscopy (AFM) and Kelvin force microscopy (KFM). Electrons and holes are injected under ambient conditions by applying different bias to a conductive AFM tip in contact with the grounded sample. A surface potential mapping of the sample by KFM is continuously carried out after charge injection. The temporal decay of injected charges and their corresponding lateral spreading are quantified. The results show that the presence of Si nanocrystals leads to a strong charge confinement.

  • Silicon nanoparticles synthesized in Sio2 pockets by stencil-masked low energy ion implantation and thermal annealing
    Superlattices and Microstructures, 2008
    Co-Authors: Jérémie Grisolia, C. Dumas, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Caroline Bonafos, M. A. F. Boogaart, J. Brugger, P. Normand
    Abstract:

    We propose an original approach called a “stencil-masked ion implantation process” for performing a spatially localized synthesis of a limited number of Si nanocrystals within a thin Sio2 Layer. In this process, the Sio2 Layer is irradiated with 1 keV silicon ions through a stencil mask containing apertures (from 100 nm to 2 μm), and subsequently thermally annealed to create Si nanocrystals. Scanning electron microscopy images show that the implanted areas mimic the mask geometry. Energy-filtered transmission electron microscopy and photoluminescence spectroscopy studies confirm that only the implanted areas are Si nanocrystal rich and light emitting. The smaller nanocrystal size detected near the edges of the implanted areas is attributed to dose reduction effects. This feature leads to a blueshift of the PL energy. Electrical properties of the structures produced are investigated using Al gate MOS capacitors. Room temperature and characteristics exhibit discrete current peaks that are associated with single-electron charging of the nanocrystals and electrostatic interaction of the trapped charges with the tunnelling current.

  • Photoluminescence spectroscopy and transport electrical measurements reveal the quantized features of Si nanocrystals embedded in an ultra thin Sio2 Layer
    physica status solidi (c), 2007
    Co-Authors: C. Dumas, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Marzia Carrada, Caroline Bonafos, Alain Claverie
    Abstract:

    In this paper, we have investigated the quantized charging features revealed by nanometer scale devices containing a 2D array of Si nanoparticles (nps) embedded into a Sio2 Layer. The Si nps were synthesized by ultra low energy ion implantation and annealing under slightly oxidizing ambient. The structural characteristics of the material (oxide thicknesses, nps size and density) have been studied by Transmission Electron Microscopy (TEM) and Energy Filtered TEM (EFTEM). Moreover, photoluminescence (PL) spectroscopy and electrical I(V) measurements using a MOS capacitor addressing only a few nps have been performed at room temperature. It is observed that, as the oxidizing annealing temperature increases, the nps size decreases and the oxide quality is restored. These features appear on the PL spectra as a blue shift of the PL red band linked to quantum confinement into nps and on the I(V) characteristics as an increase of the voltage peak width and a decrease of the main current background.

  • Influence of the thickness of the tunnel Layer on the charging characteristics of Si nanocrystals embedded in an ultra-thin Sio2 Layer
    Physica E: Low-dimensional Systems and Nanostructures, 2007
    Co-Authors: C. Dumas, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Marzia Carrada, Caroline Bonafos, Alain Claverie, M. Shalchian
    Abstract:

    In this paper, we have studied the effect of the thickness of the initial Sio2 Layer (5–7 nm) on the charge and discharge properties of a 2D array of Si nanoparticles embedded in these Sio2 Layers fabricated by ultra-low-energy ion implantation (ULE-II) and annealing. The structural characteristics of these nanocrystal-based memories (position of the nanocrystals with respect to the electrodes, size and surface density of the particles in the plane) were studied by transmission electron microscopy (TEM) and energy filtered TEM (EF-TEM). Electrical characterizations were performed at room temperature using a nano-MOS capacitor to be able to address only a few nanoparticles (nps). EFTEM gives the measurements of oxide thickness, injection, control and nps distances, size and density. I–V and I–t measurements exhibit current peaks and random telegraph signal fluctuations that can be interpreted as due to quantized charging of the nps and to some electrostatic interactions between the trapped charges and the tunnelling current. We have shown that these characteristics strongly vary with the initial oxide thickness, exhibiting several charging/discharging events for the 7-nm-thick Layer while charging events prevail in the case of 5-nm-thick Layer. These results indicate that the probability of discharging phenomena is reduced when the tunnel Layer thickness decreases.

Vincent Paillard - One of the best experts on this subject based on the ideXlab platform.

  • KFM detection of charges injected by AFM into a thin Sio2 Layer containing Si nanocrystals
    Microelectronic Engineering, 2008
    Co-Authors: C. Dumas, Laurence Ressier, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, P. Normand
    Abstract:

    Charge retention of Si nanocrystals elaborated by ultra-low energy ion implantation and thermal annealings into a thin Sio2 Layer is characterized by atomic force microscopy (AFM) and Kelvin force microscopy (KFM). Electrons and holes are injected under ambient conditions by applying different bias to a conductive AFM tip in contact with the grounded sample. A surface potential mapping of the sample by KFM is continuously carried out after charge injection. The temporal decay of injected charges and their corresponding lateral spreading are quantified. The results show that the presence of Si nanocrystals leads to a strong charge confinement.

  • Silicon nanoparticles synthesized in Sio2 pockets by stencil-masked low energy ion implantation and thermal annealing
    Superlattices and Microstructures, 2008
    Co-Authors: Jérémie Grisolia, C. Dumas, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Caroline Bonafos, M. A. F. Boogaart, J. Brugger, P. Normand
    Abstract:

    We propose an original approach called a “stencil-masked ion implantation process” for performing a spatially localized synthesis of a limited number of Si nanocrystals within a thin Sio2 Layer. In this process, the Sio2 Layer is irradiated with 1 keV silicon ions through a stencil mask containing apertures (from 100 nm to 2 μm), and subsequently thermally annealed to create Si nanocrystals. Scanning electron microscopy images show that the implanted areas mimic the mask geometry. Energy-filtered transmission electron microscopy and photoluminescence spectroscopy studies confirm that only the implanted areas are Si nanocrystal rich and light emitting. The smaller nanocrystal size detected near the edges of the implanted areas is attributed to dose reduction effects. This feature leads to a blueshift of the PL energy. Electrical properties of the structures produced are investigated using Al gate MOS capacitors. Room temperature and characteristics exhibit discrete current peaks that are associated with single-electron charging of the nanocrystals and electrostatic interaction of the trapped charges with the tunnelling current.

  • Photoluminescence spectroscopy and transport electrical measurements reveal the quantized features of Si nanocrystals embedded in an ultra thin Sio2 Layer
    physica status solidi (c), 2007
    Co-Authors: C. Dumas, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Marzia Carrada, Caroline Bonafos, Alain Claverie
    Abstract:

    In this paper, we have investigated the quantized charging features revealed by nanometer scale devices containing a 2D array of Si nanoparticles (nps) embedded into a Sio2 Layer. The Si nps were synthesized by ultra low energy ion implantation and annealing under slightly oxidizing ambient. The structural characteristics of the material (oxide thicknesses, nps size and density) have been studied by Transmission Electron Microscopy (TEM) and Energy Filtered TEM (EFTEM). Moreover, photoluminescence (PL) spectroscopy and electrical I(V) measurements using a MOS capacitor addressing only a few nps have been performed at room temperature. It is observed that, as the oxidizing annealing temperature increases, the nps size decreases and the oxide quality is restored. These features appear on the PL spectra as a blue shift of the PL red band linked to quantum confinement into nps and on the I(V) characteristics as an increase of the voltage peak width and a decrease of the main current background.

  • Influence of the thickness of the tunnel Layer on the charging characteristics of Si nanocrystals embedded in an ultra-thin Sio2 Layer
    Physica E: Low-dimensional Systems and Nanostructures, 2007
    Co-Authors: C. Dumas, Jérémie Grisolia, Arnaud Arbouet, Vincent Paillard, Gérard Benassayag, Sylvie Schamm-chardon, Marzia Carrada, Caroline Bonafos, Alain Claverie, M. Shalchian
    Abstract:

    In this paper, we have studied the effect of the thickness of the initial Sio2 Layer (5–7 nm) on the charge and discharge properties of a 2D array of Si nanoparticles embedded in these Sio2 Layers fabricated by ultra-low-energy ion implantation (ULE-II) and annealing. The structural characteristics of these nanocrystal-based memories (position of the nanocrystals with respect to the electrodes, size and surface density of the particles in the plane) were studied by transmission electron microscopy (TEM) and energy filtered TEM (EF-TEM). Electrical characterizations were performed at room temperature using a nano-MOS capacitor to be able to address only a few nanoparticles (nps). EFTEM gives the measurements of oxide thickness, injection, control and nps distances, size and density. I–V and I–t measurements exhibit current peaks and random telegraph signal fluctuations that can be interpreted as due to quantized charging of the nps and to some electrostatic interactions between the trapped charges and the tunnelling current. We have shown that these characteristics strongly vary with the initial oxide thickness, exhibiting several charging/discharging events for the 7-nm-thick Layer while charging events prevail in the case of 5-nm-thick Layer. These results indicate that the probability of discharging phenomena is reduced when the tunnel Layer thickness decreases.