Transmission electron energy-loss spectroscopy measurements of the dielectric function of Si/SiO2 multilayers

1998 ◽  
Vol 84 (12) ◽  
pp. 6827-6831 ◽  
Author(s):  
J. Keränen ◽  
T. Lepistö ◽  
L. Ryen ◽  
S. V. Novikov ◽  
E. Olsson
Keyword(s):  
Energy Loss ◽  
Electron Energy ◽  
Dielectric Function ◽  
Electron Energy Loss Spectroscopy ◽  
Transmission Electron ◽  
Electron Energy Loss

Investigation of Switching Mechanism in HfO2-Based Oxide Resistive Memories by In-Situ Transmission Electron Microscopy and Electron Energy Loss Spectroscopy

2017 ◽  
Author(s):  
T. Dewolf ◽  
D. Cooper ◽  
N. Bernier ◽  
V. Delaye ◽  
A. Grenier ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Energy Loss ◽  
Electron Energy ◽  
Electron Energy Loss Spectroscopy ◽  
Hafnium Dioxide ◽  
Switching Mechanism ◽  
Transmission Electron ◽  
Electron Energy Loss

Abstract Forming and breaking a nanometer-sized conductive area are commonly accepted as the physical phenomenon involved in the switching mechanism of oxide resistive random access memories (OxRRAM). This study investigates a state-of-the-art OxRRAM device by in-situ transmission electron microscopy (TEM). Combining high spatial resolution obtained with a very small probe scanned over the area of interest of the sample and chemical analyses with electron energy loss spectroscopy, the local chemical state of the device can be compared before and after applying an electrical bias. This in-situ approach allows simultaneous TEM observation and memory cell operation. After the in-situ forming, a filamentary migration of titanium within the dielectric hafnium dioxide layer has been evidenced. This migration may be at the origin of the conductive path responsible for the low and high resistive states of the memory.

Electron Energy-Loss Spectroscopy (EELS) of Fe-Bearing Olivine and Laihunite (an Oxidized Olivine)

2000 ◽  
Vol 6 (S2) ◽  
pp. 208-209
Author(s):  
Huifang Xu ◽  
Pingqiu Fu
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Energy Loss ◽  
Electron Energy ◽  
Electron Energy Loss Spectroscopy ◽  
Structure Refinement ◽  
Iron Formation ◽  
Transmission Electron ◽  
Electron Energy Loss

Laihunite that has distorted olivine-type structure with ferric and ferrous irons and ordered distribution of vacancies was first discovered in a high-grade metamorphosed banded iron formation (BIF) [1, 2]. The laihunite coexisting with fayalite (Fe-olivine), magnetite, quartz, ferrosilite, garnet and hedenbergite, formed in the process of oxidation of fayalite [2, 3]. The structure refinement of 1-layer laihunite shows P21/b symmetry and ordered distribution of vacancies in half M1 sites of olivine structure [2, 3]. Early high-resolution transmission electron microscopy (HRTEM) study and HRTEM image simulation of the 1-layer laihunite verified the structure refinement [4].Specimens of weakly oxidized fayalite and laihunite containing fayalite islands collected from Xiaolaihe and Menjiagou of Liaoning Province, NE China, have been studied using selected area electron diffraction (SAED), high-resolution transmission electron microscopy (HRTEM), electron energy-loss spectroscopy (EELS), and X-ray energy-dispersive spectroscopy.

A Novel Technique for Determining Local Dielectric Function During Ferroelectric to Paraelectric Phase Transformation in Barium Titanate with a Transmission Eels

1995 ◽  
Vol 404 ◽  
Author(s):  
Kalpana S Katti ◽  
Maoxu Qian ◽  
Mehmet Sarikaya
Keyword(s):  
Phase Transformation ◽  
Barium Titanate ◽  
Energy Loss ◽  
Electron Energy ◽  
Dielectric Function ◽  
Optical Parameters ◽  
Edge Structure ◽  
Transmission Electron ◽  
Electron Energy Loss

AbstractIn this work a transmission electron microscopy (TEM) technique was used in obtaining local dielectric properties calculated from optical parameters for dynamic investigation of the effect of cubic to tetragonal phase transformation in barium titanate. In order to obtain in situ local dielectric during phase transformation, Kramers-Kronig relations were applied using the transmission electron energy loss (EELS) measurements. The optical excitations in the EELS spectra were consistent with the band structure results. The Re (1/ε) (real part of the dielectric function) obtained from the energy loss data indicated a change at the phase transformation. A broadening of the valence plasmon excitation suggested an order-disorder nature to the cubic to tetragonal transformation. In situ electron energy loss near edge structure (ELNES) studies from 500–700 eV energy range near the O-K edge exhibited a pre-edge feature that is associated with the Ti-L1, edge which further indicates an order-disorder nature to the phase transformation. The significance of the results is discussed.

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