Cathodoluminescence analysis on GaN/AlN nanowires

Cathodoluminescence analysis on GaN/AlN nanowires
Data courtesy of Dr. R. Williams, Ohio State University.

a) Dark field STEM image of GaN/AlN heterostructure nanowire with nominally 3 nm thick GaN quantum wells and 4 nm thick AlN barrier layers; GaN is bright in DF image; (b) Cathodoluminescence (CL) spectrum-image acquired from region indicated by green rectangle in (a) with intensity at 491 ±10 nm displayed; (c) Single CL spectrum extracted from the spectrum-image at point 2 as displayed in (b); (d) Projection of the CL spectrum with information along y-axis (radial axis of the nanowire) summed into a single value.

EELS analysis of metal segregation across grain boundary in Yttria-stabilized Zirconia (YSZ) – investigating oxygen vacancies

EELS analysis of metal segregation across grain boundary in Yttria-stabilized Zirconia (YSZ) – investigating oxygen vacancies
Paolo Longo, Ph.D., Gatan, Inc. Microscope and sample courtesy of Dr. Maria Varela at Oak Ridge National Lab, Oak Ridge, TN

EELS data were acquired using a probe-corrected NION Ultrastem 200 TEM/STEM microscope equipped with C-FEG emission gun and a fully loaded Enfinium™ ER system.

Methods

Voltage: 200 kV; data taken in STEM mode; EELS core-loss spectrum (400 – 2400 eV): 40 ms; dataset size: 128 x 128 pixels

Fast EELS analysis of AlNiCo based metal alloy for magnetic purposes

Fast EELS analysis of AlNiCo based metal alloy for magnetic purposes
Paolo Longo, Ph.D., Gatan, Inc. Sample courtesy of Dr. Li Zhou at Ames Lab, Iowa

EELS data taken using a FEI F20 TEM/STEM microscope equipped with S-FEG emission gun and a fully loaded GIF Quantum® ER system.

Methods

Voltage: 200 kV; data taken in STEM mode; EELS spectrum (300 – 2300 eV) exposure time: 8 ms; total exposure time: <1 min

Fast EELS analysis of metals in a blood cell attacked by the malaria parasite

Fast EELS Analysis of Metals in a Blood Cell
Paolo Longo, Ph.D., Gatan, Inc.

EELS data taken using a FEI F20 TEM/STEM microscope equipped with S-FEG emission gun and a fully loaded GIF Quantum® ER system.

Methods

Voltage: 200 kV; data taken in STEM mode; EELS spectrum (80 – 2080 eV) exposure time: 5 ms; dataset size: 216 x 272 pixels; total exposure time: 4 min

Fast DualEELS analysis of the distribution of Pd particles and their chemistry in zeolite

Fast DualEELS analysis of the distribution of Pd particles and their chemistry in zeolite
Paolo Longo, Ph.D., Gatan, Inc.

The EELS analysis shows how Pd particles chemically interact with support.

Atomic DualEELS analysis of CaFeO2,5 Brownmillerite structure—Investigating the presence of oxygen vacancies

Atomic DualEELS analysis of CaFeO2,5 Brownmillerite structure—Investigating the presence of oxygen vacancies
Paolo Longo, Ph.D., Gatan, Inc. Sample courtesy of Professor Ramachandra Rao at Indian Institute of Technology, Chennai Madras, India Microscope courtesy of Dr. Giuseppe Nicotra at IMM-CNR, Catania, Italy

Fe-O atoms are arranged in alternating tetrahedral and octahedral planes that can be distinguished looking at the fine structure of the O K-edge at 532 eV. Hybridization between the O and Fe orbitals is different depending on the way the atoms are arranged, and changes can be seen in the O K-edge at 532 eV in the EELS spectrum.

First atomic EELS map acquired during volcano eruption

First atomic EELS map acquired during volcano eruption
Paolo Longo, Ph.D., Gatan, Inc. Sample courtesy of Dr. P. Rice and Dr. T. Topuria at IBM (Almaden), San Jose, CA Microscope courtesy of Dr. Giuseppe Nicotra, IMM-CNR, Catania, Italy

The lab where EELS maps were taken is situated at the slopes of Mount Etna in Sicily, Italy. Mount Etna is the highest active volcano in Europe. The EELS elemental maps were taken at high speed during major volcano eruption, as shown in the volcano webcam photograph above the maps.

Fast atomic EELS analysis across the GaN/AlGaN interface

Fast atomic EELS analysis across the GaN/AlGaN interface
Paolo Longo, Ph.D., Gatan, Inc. Sample courtesy of Dr. Giuseppe Nicotra at IMM-CNR, Catania, Italy Microscope courtesy of Dr. Giuseppe Nicotra at IMM-CNR, Catania, Italy

Methods

probe-corrected ARM 200F TEM/STEM microscope
C-FEG emission gun
GIF Quantum® ER system
voltage: 200 kV
data taken in STEM mode
EELS core-loss spectrum (200 – 2200 eV) exposure time: 10 ms
b
eam current: 45 pA
d
ataset size: 250 x 250 pixels
t
otal exposure time: 11 min

Fast Joint EELS / EDS color map of a SrTiO3 crystal

Fast Joint EELS / EDS color map of a SrTiO3 crystal
Paolo Longo, Ph.D., Gatan, Inc. Sample courtesy of Dr. Yan Xin at Florida State University, Tallahassee, FL Microscope courtesy of Professor Gerald Kothleitner, TU-Graz, Austria Acknowledgement to Dr. Arno Meingast at CCEM, TU-Graz, Austria for helping set up microscope for experiment.

Methods

probe-corrected FEI Titan TEM/STEM microscope
X-FEG emission gun
GIF Quantum® ERS system
four quadrant SDD EDS detectors (FEI Chemistem)
Ti (green); Sr (red)
v
oltage: 200 kV
d
ata taken in STEM mode
EELS low core-loss spectrum (300 – 2300 eV): 10 ms
dataset size: 70 x 57 pixels

32 nm Transistor device

Fast joint EELS / EDS color map across a 32 nm transistor device
Paolo Longo, Ph.D., Gatan, Inc. Sample courtesy of Dr. Pavel Potapov at Global Foundries, Dresden, Germany Microscope courtesy of Dr. P. Rice and Dr. T. Topuria at IBM (Almaden), San Jose, CA Acknowledgements to Dr. P. Rice and Dr. T. Topuria at IBM (Almaden), San Jose, CA for helping set up microscope for experiment.

Methods

probe-corrected Jeol ARM 200 TEM/STEM microscope
C-FEG emission gun
GIF Quantum® ER system
Jeol Centurio SDD EDS detector (0.98 sr)
O K at 532 eV (red); Ti L at 456 eV (green); Ni L at 855 eV (light blue); N K at 401 eV (yellow); Hf M at 1662 eV (purple)
voltage: 200 kV
data taken in STEM mode
EELS core-loss spectrum (300 – 2300 eV): 1.5 ms

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