Scanning transmission electron microscopy strain measurement from millisecond frames of a direct electron charge coupled device

Müller, Knut; Ryll, H.; Ordavo, I.; Ihle, Sebastian; Strüder, L.; Volz, Kerstin; Zweck, Josef; Soltau, H.; Rosenauer, A.

doi:10.1063/1.4767655

Cited by 69 publications

(48 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Radial gradient maximization is another method used [21,8,22], in which concentric circles or ellipses are placed around an estimated disk center and their rotational averages are calculated. Since most disks have sharp edges, when the difference between the rotational average of concentric shapes are a maximum, the concentric shapes are properly placed around the center of the disk.…”

Section: Methods For Determining Diffraction Disk Positionsmentioning

confidence: 99%

Optimizing disk registration algorithms for nanobeam electron diffraction strain mapping

et al. 2017

View full text Add to dashboard Cite

Scanning nanobeam electron diffraction strain mapping is a technique by which the positions of diffracted disks sampled at the nanoscale over a crystalline sample can be used to reconstruct a strain map over a large area. However, it is important that the disk positions are measured accurately, as their positions relative to a reference are directly used to calculate strain. In this study, we compare several correlation methods using both simulated and experimental data in order to directly probe susceptibility to measurement error due to non-uniform diffracted disk illumination structure. We found that prefiltering the diffraction patterns with a Sobel filter before performing cross correlation or performing a square-root magnitude weighted phase correlation returned the best results when inner disk structure was present. We have tested these methods both on simulated datasets, and experimental data from unstrained silicon as well as a twin grain boundary in 304 stainless steel.

show abstract

Section: Methods For Determining Diffraction Disk Positionsmentioning

confidence: 99%

Optimizing disk registration algorithms for nanobeam electron diffraction strain mapping

et al. 2017

View full text Add to dashboard Cite

show abstract

“…While it is possible to perform quasistatic experiments using scanning nanobeam diffraction over these relatively long periods of time, 13 it is not experimentally practical for continuous in situ TEM experiments that must be performed without stopping the experiment. Recently, the use of millisecond acquisition times of direct electron detectors has been shown to retain the precision of the strain measurement 14 and we have recently demonstrated that it can be used to acquire strain maps of a large field of view. 12 Here, we take advantage of a Gatan K2 IS direct electron detector operating at a frame rate of 400 f/s.…”

mentioning

confidence: 99%

Local and transient nanoscale strain mapping during in situ deformation

Gammer

Kacher

Czarnik³

et al. 2016

Applied Physics Letters

View full text Add to dashboard Cite

The mobility of defects such as dislocations controls the mechanical properties of metals. This mobility is determined both by the characteristics of the defect and the material, as well as the local stress and strain applied to the defect. Therefore, the knowledge of the stress and strain during deformation at the scale of defects is important for understanding fundamental deformation mechanisms. Here, we demonstrate a method of measuring local stresses and strains during continuous in situ deformation with a resolution of a few nanometers using nanodiffraction strain mapping. Our results demonstrate how large multidimensional data sets captured with high speed electron detectors can be analyzed in multiple ways after an in situ TEM experiment, opening the door for true multimodal analysis from a single electron scattering experiment.

show abstract

“…5,6 Therefore, for next-generation technology, it is required to monitor the layout-dependent strain behavior with high precision at nanometer-scale spatial resolutions. Although various tools have been applied to the measurement of strain fields in semiconductor structures, 4,[7][8][9][10][11][12][13][14][15][16][17] there have been relatively few experimental results regarding studying the effect of the channel length on the strain field induced in semiconductor device structures. 18 In this study, we have applied scanning moiré fringe (SMF) imaging, 19 which is a high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM)-based technique, to quantitatively measure the strain field in transistors with various channel lengths down to 25 nm.…”

mentioning

confidence: 99%

Channel-Length-Dependence of Strain Field in Transistor Studied via Scanning Moire Fringe Imaging

Kim

Lee

Oshima

et al. 2013

ECS Solid State Letters

View full text Add to dashboard Cite

We have applied scanning moiré fringe (SMF) imaging to the quantitative measurement of the strain introduced in n-type channel transistors with embedded SiC in the source and drain. The tensile strain parallel to the channels was reveal with a nano-meter scale spatial resolution. We investigated the strain field in transistors with various channel lengths scaled down to 25 nm, and found that the strain increases up to 0.7% as the channel length shrinks to 35 nm. However, the strain in the channel decreases to 0. 55% as the channel length is scaled from 35 nm down to 25 nm. Strain engineering is routinely applied in the fabrication of advanced semiconductor devices to enhance the mobility of the carriers in transistors.1,2 The mobility of electrons or holes is boosted when the channel in a transistor is under either a tensile or compressive strain, respectively. The Si 1−x C x embedded in the source/drain region has been used for n-type field effect transistors.3 The lattice parameter of Si 1−x C x with a carbon concentration of about 1% is smaller than that of pure Si. Thus, a compressive stress is formed in the source/drain region, which in turn induces a tensile strain in the n-type channel. 4 Since the electrical performance of the device is greatly influenced by the strain field induced in the channel region, it is required to control the strain field for optimum manufacturing processing. Furthermore, with decrease in the size of modern semiconductor devices, the strain field in the semiconductor devices tends to be strongly influenced by layout design parameters such as the channel length and the geometry of the source and drain regions. 5,6 Therefore, for next-generation technology, it is required to monitor the layout-dependent strain behavior with high precision at nanometer-scale spatial resolutions. Although various tools have been applied to the measurement of strain fields in semiconductor structures, 4,7-17 there have been relatively few experimental results regarding studying the effect of the channel length on the strain field induced in semiconductor device structures. 18In this study, we have applied scanning moiré fringe (SMF) imaging, 19 which is a high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM)-based technique, to quantitatively measure the strain field in transistors with various channel lengths down to 25 nm. SMF imaging is a recently developed method that can measure strain fields at a high spatial resolution in the nanometer scale. [20][21][22] In the HAADF-STEM experiment, the SMFs appear when the scanning grating size d s is close to the crystal lattice spacing d l . Figure 1a shows the strained lattice spacing d l that increases from the bottom to the top of the pattern. Figure 1b Fig. 1c. 22 Because the SMF spacing d SMF changes very sensitively to the variation in the lattice plane spacing d l , the strain field can be obtained by substituting the measured d SMF and a calibrated value of d s in the formula for the width of the translational moiré ...

show abstract

Scanning transmission electron microscopy strain measurement from millisecond frames of a direct electron charge coupled device

Cited by 69 publications

References 27 publications

Optimizing disk registration algorithms for nanobeam electron diffraction strain mapping

Optimizing disk registration algorithms for nanobeam electron diffraction strain mapping

Local and transient nanoscale strain mapping during in situ deformation

Channel-Length-Dependence of Strain Field in Transistor Studied via Scanning Moire Fringe Imaging

Contact Info

Product

Resources

About