SONOS memory devices with ion beam modified nitride layers

2012 ◽  
Vol 1430 ◽  
Author(s):  
D. Simatos ◽  
P. Dimitrakis ◽  
V. Ioannou-Sougleridis ◽  
P. Normand ◽  
K. Giannakopoulos ◽  
...  
Keyword(s):  
Room Temperature ◽  
Loss Rate ◽  
Ion Beam ◽  
Memory Window ◽  
Electron Loss ◽  
Gate Stacks ◽  
Pulse Regime ◽  
Transmission Electron ◽  
Nitride Layers ◽  
Nitride Oxide

ABSTRACTIn this work we examine the development of ion beam modified oxide-nitride-oxide structures formed by low-energy (1 keV) implantation of Si, N and Ar ions (1x1016 ions/cm2) into oxide-nitride gate stacks and subsequent wet-oxidation to form the blocking oxide. Transmission electron microscopy indicates that the thickness of the blocking oxide layer is strongly affected by the implantation process going from 1 nm (non-implanted sample) to 4-5 nm (N and Ar implants) and 7.5 nm (Si implant). The Si implanted stacks exhibit the highest attainable memory window (∼ 8.5 V for a 1 ms pulse regime), which involve both electron and hole storage. In contrast the thinner blocking oxide that develops to the nitrogen and argon implanted stacks limits the memory window which is due only to electron trapping. Room temperature charge retention measurements of the programming state reveal that the electron loss rate is faster in samples implanted with Si than N, allowing for a memory window of 1.7 V and 2.5 V respectively after ten years extrapolation. This retention behavior is mainly attributed to the different nature of the traps generated in the implanted materials.

Room Temperature Synthesis of Cu2O Nanospheres: Optical Properties and Thermal Behavior

2014 ◽  
Vol 21 (1) ◽  
pp. 108-119 ◽  
Author(s):  
Daniela Nunes ◽  
Lídia Santos ◽  
Paulo Duarte ◽  
Ana Pimentel ◽  
Joana V. Pinto ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Thermal Behavior ◽  
Room Temperature ◽  
Diffuse Reflectance Spectroscopy ◽  
Ion Beam ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron

AbstractThe present work reports a simple and easy wet chemistry synthesis of cuprous oxide (Cu2O) nanospheres at room temperature without surfactants and using different precursors. Structural characterization was carried out by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy coupled with focused ion beam and energy-dispersive X-ray spectroscopy. The optical band gaps were determined from diffuse reflectance spectroscopy. The photoluminescence behavior of the as-synthesized nanospheres showed significant differences depending on the precursors used. The Cu2O nanospheres were constituted by aggregates of nanocrystals, in which an on/off emission behavior of each individual nanocrystal was identified during transmission electron microscopy observations. The thermal behavior of the Cu2O nanospheres was investigated with in situ X-ray diffraction and differential scanning calorimetry experiments. Remarkable structural differences were observed for the nanospheres annealed in air, which turned into hollow spherical structures surrounded by outsized nanocrystals.

On the Oriented Growth and Optical Property of ZnO Thin Films Deposited on NaCl (001) Substrate by Ion Beam Sputtering

2010 ◽  
Vol 121-122 ◽  
pp. 52-57
Author(s):  
Shih Wei Mao ◽  
Jung Hsiung Shen ◽  
Der Shin Gan ◽  
Hsing Lu Huang ◽  
Sung Wei Yeh
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Ion Beam ◽  
Ion Beam Sputtering ◽  
Temperature Dependent ◽  
Epitaxial Relationship ◽  
Oriented Growth ◽  
Transmission Electron ◽  
Beam Sputtering ◽  
High Resolution Tem

Temperature dependent oriented growth of ZnO thin film deposited on NaCl (001) substrates using ion beam sputtering was studied by transmission electron microscopy (TEM). Thin films showing a texture due to parallel epitaxy with NaCl (001) as deposited at 100 oC, whereas thin films deposited at 400 oC can form a texture. The microstructure and the epitaxial relationship with the NaCl (001) plane were studied by a high-resolution TEM. The possible causes for the orientation changed with temperature are discussed. The optical transparency of the nanofilms grown from room temperature to 400 oC was measured.

Evolution of Cubic FeSi2 in Si upon Thermal Annealing

1993 ◽  
Vol 311 ◽  
Author(s):  
X.X. Lin ◽  
J. Desimoni ◽  
H. Bemas ◽  
Z. Liliental-Weber ◽  
J. Washburn
Keyword(s):  
Electron Microscopy ◽  
Thermal Annealing ◽  
Room Temperature ◽  
Ion Beam ◽  
Cubic Phase ◽  
Precipitate Coarsening ◽  
Transmission Electron ◽  
Higher Temperature ◽  
Induced Crystallization ◽  
Fe Implantation

ABSTRACTCubic FeSi2 precipitates were produced in Si (001) wafers by Fe implantation at room temperature, followed by ion beam-induced crystallization at 320°C, and their stability upon thermal annealing was examined by transmission electron microscopy. We found that the cubic phase remains relatively stable for a 650°C anneal, but the precipitates tend to change from an aligned to a twinned orientation with respect to the Si matrix. For higher temperature (800 and 900°C) anneals, most of the precipitates are transformed into β-FeSi2, accompanied by substantial precipitate coarsening. For platelet-shaped precipitates, the coarsening activation energy was determined to be 3.48 eV.

Formation and Transformation of Amorphous Silicide Alloys

1983 ◽  
Vol 31 ◽  
Author(s):  
K.N. Tu ◽  
T. Tien ◽  
S.R. Herd
Keyword(s):  
Vapor Deposition ◽  
Room Temperature ◽  
Ion Beam ◽  
Conductivity Measurement ◽  
Rapid Quenching ◽  
Slow Heating ◽  
Electrical Conductivity Measurement ◽  
Ion Beam Mixing ◽  
Transmission Electron ◽  
Amorphous Si

ABSTRACTAmorphous silicide films can be formed by rapid quenching using techniques of vapor deposition and ion beam mixing and also by slow heating using solid state interdiffusion and reaction. For example, amorphous TaSi2 films can be formed by sputtering or dual electron guns co-deposition. Amorphous Pt2Si3 films have been produced by mixing PtSi and Si at room temperature with an ion beam at about 100 to 300keV. Recently, an amorphous Rh-Si alloy phase has been made by slowly heating to 300°C a very thin crystalline Rh films (∼50Å) on amorphous Si. The formation and crystallization behavior of these amorphous silicide alloys has been studied by transmission electron microscopy and electrical conductivity measurement.

Dendritic Growth During Phase Transformation in Ni-Mo System Induced by Ion Beam

1986 ◽  
Vol 74 ◽  
Author(s):  
B. X. Liu ◽  
L. J. Huang ◽  
C. H. Shang
Keyword(s):  
Dendritic Growth ◽  
Room Temperature ◽  
Ion Beam ◽  
Cluster Formation ◽  
Beam Current ◽  
Beam Current Density ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Amorphous Phase Formation

AbstractMultilayered Ni-Mo films were irradiated by 200keV Xe ions at room temperature to various doses. The beam current density was confined to be less than lμA/cm2 to avoid overheating. The experimental evidences from X-ray diffraction, electrical resistivity, as well 4 as Rutherford Backscattering, indicate that a dose of 7 × 1014/cm2 was the critical one for uniform mixing of the layers and amorphous phase formation in Ni65 Mo35 films. Under this critical dose, various dendritic patterns were formed as revealed by bright field transmission electron microscopy. The microscopic mechanisms of the ion induced dendritic growth are attributed to the cluster formation and the aggregation of the formed clusters.

Toughening of Brittle Materials by Dislocation Cells

2001 ◽  
Vol 7 (S2) ◽  
pp. 420-421
Author(s):  
H. Saka ◽  
W.-J. Moon ◽  
S. Horiuchi ◽  
S. Uchimura
Keyword(s):  
Fracture Toughness ◽  
Room Temperature ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Brittle Materials ◽  
Thin Foil ◽  
Vickers Indentation ◽  
Transmission Electron ◽  
Dislocation Cells ◽  
Metallurgical Processes

Many attempts have been made to improve the fracture toughness of brittle materials such as ceramics. Most of the methods developed so far make use of metallurgical processes, for example, phase transformation, refining of grains, formation of composite materials. However, these methods can not be applied universally to brittle materials which do not have such a useful metallurgical processes.Moon and Saka (1) recently showed that the fracture toughness Klc of a YAG single crystal the sub-surface of which is damaged by micro-Vickers indentation at room temperature, followed by annealing at high temperatures is improved by a factor 2 from 1.13 to 2.26MPam1/2. The fracture toughness Klc was evaluated by measuring the length of cracks which initiate at the corner of Vickers indentation(2). Transmission electron microscopy of the subsurface reveals the healing of cracks introduced by room-temperature indentation and formation of dislocation cells. The thin foil specimens were prepared using a focused ion beam (FIB) technique(3).

Oxide-nitride-oxide Dielectric Stacks with Embedded Si-nanoparticles Fabricated by Low-energy Ion-beam-synthesis

2007 ◽  
Vol 997 ◽  
Author(s):  
Vassilis Ioannou-Sougleridis ◽  
Panagiotis Dimitrakis ◽  
Vassilios Em. Vamvakas ◽  
Pascal Normand ◽  
Caroline Bonafos ◽  
...  
Keyword(s):  
Ion Beam ◽  
Synthesis Method ◽  
Electrical Characterization ◽  
Charge Trapping ◽  
Differential Resistance ◽  
Low Energy ◽  
Si Nanocrystals ◽  
Ion Beam Synthesis ◽  
Nitride Layers ◽  
Nitride Oxide

AbstractThis work reports on the formation of Si-nanocrystals within silicon nitride layers by low-energy Si ion implantation. Electrical characterization of oxide/Si-nanocrystal-nitride/oxide dielectric stacks demonstrates regions of negative differential resistance at low-fields. In addition, the memory characteristics in terms of charge trapping, write/erase response and retention properties of the dielectric stacks were recorded. The results indicate the large potential of the low-energy ion beam synthesis method in nitride memory technology.

Yield of InxGa1-xAs Superlattices Under Bending and Nanoindentation

2003 ◽  
Vol 778 ◽  
Author(s):  
Stephen J. Lloyd ◽  
Ken M.Y. P'ng ◽  
Andy J. Bushby ◽  
David J. Dunstan ◽  
William J. Clegg
Keyword(s):  
Room Temperature ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Misfit Dislocations ◽  
Thin Sections ◽  
Transmission Electron ◽  
Inp Substrate ◽  
Highly Strained ◽  
Inp Substrates ◽  
Coherency Strains

AbstractA series of InxGa1-xAs superlattices grown on InP substrates with differing coherency strains have been deformed by bending at 500°C and by nanoindentation at room temperature. The deformation was characterised by transmission electron microscopy through examination of thin sections machined in a focused ion beam microscope. The bent samples sheared along {111} planes, and the most highly strained samples partially relaxed through the formation of misfit dislocations. Under indentation the majority of the plastic strain in the multilayers is accommodated by twinning whereas no twins were observed under indents in the InP substrate. The overall dimensions of the plastic zone increased linearly with indent load.

Microstructure of Niobium Films Oriented By Non-Normal Incidence Ion Bombardment During Growth

1985 ◽  
Vol 51 ◽  
Author(s):  
J.M.E. Harper ◽  
D.A. Smith ◽  
L.S. Yu ◽  
J.J. Cuomo
Keyword(s):  
Room Temperature ◽  
Film Growth ◽  
Ion Beam ◽  
Normal Incidence ◽  
Ion Bombardment ◽  
Fiber Texture ◽  
Thin Film Growth ◽  
Transmission Electron ◽  
Glancing Angle ◽  
Beam Orientation

ABSTRACTWe demonstrate that non-normal incidence ion bombardment applied during thin film growth has a pronounced alignment effect on crystallographic orientation. Restricted fiber texture is achieved in Nb films deposited at room temperature onto amorphous silica substrates with simultaneous 200 eV Ar+ ion bombardment at 20 degrees from glancing angle. Xray pole figure measurements and transmission electron diffraction show that the alignment direction is a channeling direction for the incident ions between (110) planes. The degree of alignment increases linearly with the fraction resputtered by the ion beam. Recommendations are given for optimizing this ion beam orientation effect.

Size Effect in Nix(MgO)100-X Nanocomposites

2010 ◽  
Vol 168-169 ◽  
pp. 361-364 ◽  
Author(s):  
A.A. Grebennikov ◽  
O.V. Stognei
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Curie Temperature ◽  
Size Effect ◽  
Room Temperature ◽  
Ion Beam ◽  
Ion Beam Sputtering ◽  
Nanostructured Composite ◽  
Transmission Electron ◽  
Beam Sputtering

The possibility of obtaining a nanostructured composite in the Ni-Mg-O system by ion-beam sputtering has been investigated. The structural, magnetic and magnetoresistive properties of obtained samples have been investigated in a wide concentration range. The presence of the nanostructure in the obtained samples with Ni nanogranules (2-3 nm) has been confirmed by transmission electron microscopy. There is no observation of any magnetic or magnetoresistive properties at room temperature in the Nix(MgO)100-x composites. These properties were observed at 77 K. The obtained data mean that Curie temperature of the Ni nanogranules is lower then 298 K. This is due to small size of nickel granules and low value of exchange interaction energy in nickel.

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