Application of Aberration-Corrected TEM and Image Simulation to Nanoelectronics and Nanotechnology

Korgel, Brian A.; Lee, D.C.; Hanrath, Tobias; Yacamán, M. José; Thesen, Alexander; Matijevic, M.; Kilaas, R.; Kisielowski, C.; Diebold, Alain C.

doi:10.1109/tsm.2006.884713

Cited by 18 publications

(15 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…High‐resolution transmission electron microscopy (HRTEM) imaging and electron diffraction are commonly used to determine the crystal structure, growth direction,12, 13 and defect structure in Si nanowires 5, 10, 14–17. Particularly common are observations of ⅓{422} and fractional {111} reflections in the [111] and [110] zone axes, respectively.…”

Section: Introductionmentioning

confidence: 99%

Atomic Structural Analysis of Nanowire Defects and Polytypes Enabled Through Cross‐Sectional Lattice Imaging

Hemesath

Schreiber

Kisielowski

et al. 2012

Small

View full text Add to dashboard Cite

Correlated transmission electron microscopy imaging, electron diffraction, and Raman spectroscopy are used to investigate the structure of Si nanowires with planar defects. In addition to plan-view imaging, individual defective nanowires are imaged in axial cross-section at specific locations selected in plan-view imaging. This correlated characterization approach enables definitive identification of complex defect structures that give rise to diffraction patterns that have been misinterpreted in the literature. Conclusive evidence for the 9R Si polytype is presented, and the atomic structure of this phase is correlated with kinematically-forbidden reflections in Si diffraction patterns. Despite striking similarities between imaging and diffraction data from twinned nanowires and the 9R polytype, clear distinctions between the structures can be made. Finally, the structural origins of ⅓{422} reflections in Si [111] diffraction patterns are identified.

show abstract

Section: Introductionmentioning

confidence: 99%

Atomic Structural Analysis of Nanowire Defects and Polytypes Enabled Through Cross‐Sectional Lattice Imaging

Hemesath

Schreiber

Kisielowski

et al. 2012

Small

View full text Add to dashboard Cite

show abstract

“…For very thin fcc crystals it has been proposed that at the surface the ABCABC cubic stacking can be incomplete, therefore some of the crystal can be described by the 2H wurtzite phase, which can create extra diffraction spots 21 . This idea was also used for NWs 22 . Although this hypothesis can explain the experimentally observed EDP's/HRTEM images successfully, this does not exclude the presence of defects.…”

Section: Introductionmentioning

confidence: 99%

Hidden defects in silicon nanowires

et al. 2011

View full text Add to dashboard Cite

Recent publications have reported the presence of hexagonal phases in Si nanowires. Most of these reports were based on 'odd' diffraction patterns and HRTEM images , -'odd' means that these images and diffraction patterns could not be obtained on perfect silicon crystals in the classical diamond cubic structure. We analyze the origin of these 'odd' patterns and images by studying the case of various Si nanowires grown using either Ni or Au as catalyst in combination with P or Al doping. Two models could explain the experimental results : (i) the presence of an hexagonal phase or (ii) the presence of defects that we call 'hidden' defects because they cannot be directly observed on most images. We show that in many cases one direction of observation is not sufficient to distinguish between the two models. Several directions of observations have to be used. Secondly, conventional TEM images i.e. bright field two beam and dark field images, are of great value in the identification of 'hidden' defects. In addition, slices of nanowires perperpendicular to the growth axis can be very useful. In the studied nanowires no hexagonal phase with long range order is found and the 'odd' images and diffraction patterns are mostly due to planar defects causing superposition of different crystal grains. Finally, we show that in Raman experiments the defect rich NWs can give rise to a Raman peak shifted to 504-511 cm −1 with respect to the Si bulk peak at 520 cm −1 , indicating that Raman cannot be used to identify an hexagonal phase.

show abstract

“…Recent simulation of silicon nanowires illustrates that even a seemingly simple task such as location of the edge of a nanowire sample requires aberration corrected lens and careful experimental procedure. (11) …”

Section: II Aberration Corrected Transmission Electron Microscopymentioning

confidence: 99%

Survey of characterization and metrology for nanoelectronics

Diebold

2008

2008 IEEE International Reliability Physics Symposium

Self Cite

View full text Add to dashboard Cite

Advances in process technology enable high volume manufacture of integrated circuits with nano-scale transistor and interconnect technology. This fabrication capability results in the availability of a great range of nano-scale materials and structures such as nano-tubes, thin films, nano-dots, and nanowires. Many of these materials are under consideration as the material for Beyond CMOS switches. There are two themes emphasized in this paper. First, materials exhibit new phenomena such as quantum confinement at nano-scale dimensions. Measurements not only observe these phenomena, determination of the dimensions of nanoscale materials requires understanding of these phenomena. Second, simulation and modeling at nano-scale dimensions is critical to both device operation and metrology. This extended abstract reviews the materials characterization and metrology methods necessary for measuring materials properties. This abstract covers several of the many measurement methods necessary for nanoscale characterization and metrology. I. The Impact of Quantum Phenomena on Optical Metrology and X-Ray Photoelectron SpectroscopyMaterials characterization of nano-scale materials has proven the existence of quantum confinement or quantum size effects (QSE). The observation of QSE in thin metal films using X-ray Photoelectron Spectroscopy is well known to the surface science community.(1) When the thickness of metal film is small enough, electron motion is confined in one dimension.The phase accumulation model correctly describes quantization of new energy level of the free electron gas by the film thickness.(2) When a metal film is thin enough and the interface between the metal and substrate are smooth enough, the extra energy levels can be observed by XPS at room temperature.Recently, we have shown that optical methods can also observe quantum confinement in ultra-thin silicon semiconductor films. The first step in identifying changes in optical properties, especially the dielectric function, is demonstrating that the data is not due to other phenomena such as stress. We observed a blue shift in the E1 critical point of ultra-thin silicon and show that it can be attributed to quantum confinement.(3) It is important to note that energy shifts in E1 smaller than KT can be observed optically. II.. Aberration Corrected Transmission Electron MicroscopyRoutinely producing high quality images is critical to nanoscale materials characterization. It is well known that image quality in electron and optical microscopy suffers from lens aberration. Electron lens aberration in high resolution transmission electron microscopy (HRTEM) results in delocalization of critical information. For example, lattice fringes can be observed to extend beyond the actual grain boundary in poly-crystalline samples. Delocalization also obscures interfacial features. The location of the last plane of atoms at an interface is typically difficult to observe.In scanning TEM (STEM), the spatial resolution of images and the ability to determine the location of t...

show abstract

Application of Aberration-Corrected TEM and Image Simulation to Nanoelectronics and Nanotechnology

Cited by 18 publications

References 24 publications

Atomic Structural Analysis of Nanowire Defects and Polytypes Enabled Through Cross‐Sectional Lattice Imaging

Atomic Structural Analysis of Nanowire Defects and Polytypes Enabled Through Cross‐Sectional Lattice Imaging

Hidden defects in silicon nanowires

Survey of characterization and metrology for nanoelectronics

Contact Info

Product

Resources

About