Measurement of curvature radius using phase retrieval with volume speckle field

2010 ◽  
Author(s):  
Mingguang Shan ◽  
Pei Zhi ◽  
Zhi Zhong ◽  
Bo Zhu
Keyword(s):  
Phase Retrieval ◽  
Curvature Radius ◽  
Speckle Field

Aperture synthesis in phase retrieval using a volume-speckle field

2007 ◽  
Vol 32 (7) ◽  
pp. 733 ◽  
Author(s):  
P. Almoro ◽  
G. Pedrini ◽  
W. Osten
Keyword(s):  
Phase Retrieval ◽  
Aperture Synthesis ◽  
Speckle Field

Comprehensive characterization of TSV etching performance with phase-contrast X-ray microtomography

2020 ◽  
Vol 27 (4) ◽  
pp. 1023-1032 ◽  
Author(s):  
Ke Li ◽  
Biao Deng ◽  
Haipeng Zhang ◽  
Fucheng Yu ◽  
Yanling Xue ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Phase Contrast ◽  
Phase Retrieval ◽  
Comprehensive Evaluation ◽  
Linear Interpolation ◽  
Curvature Radius ◽  
Element Analysis ◽  
X Ray ◽  
3D Microstructure

Comprehensive evaluation of through-silicon via (TSV) reliability often requires deterministic and 3D descriptions of local morphological and statistical features of via formation with the Bosch process. Here, a highly sensitive phase-contrast X-ray microtomography approach is presented based on recorrection of abnormal projections, which provides comprehensive and quantitative characterization of TSV etching performance. The key idea is to replace the abnormal projections at specific angles in principles of linear interpolation of neighboring projections, and to distinguish the interface between silicon and air by using phase-retrieval algorithms. It is demonstrated that such a scheme achieves high accuracy in obtaining the etch profile based on the 3D microstructure of the vias, including diameter, bottom curvature radius, depth and sidewall angle. More importantly, the 3D profile error of the via sidewall and the consistency of parameters among all the vias are achieved and analyzed statistically. The datasets in the results and the 3D microstructure can be applied directly to a reference and model for further finite element analysis. This method is general and has potentially broad applications in 3D integrated circuits.

3D shape measurement using deterministic phase retrieval and a partially developed speckle field

2012 ◽  
Author(s):  
Percival F. Almoro ◽  
Laura Waller ◽  
Mostafa Agour ◽  
Claas Falldorf ◽  
Giancarlo Pedrini ◽  
...  
Keyword(s):  
Phase Retrieval ◽  
Shape Measurement ◽  
Speckle Field ◽  
3D Shape ◽  
3D Shape Measurement

scholarly journals Enhanced deterministic phase retrieval using a partially developed speckle field

2012 ◽  
Vol 37 (11) ◽  
pp. 2088 ◽  
Author(s):  
Percival F. Almoro ◽  
Laura Waller ◽  
Mostafa Agour ◽  
Claas Falldorf ◽  
Giancarlo Pedrini ◽  
...  
Keyword(s):  
Phase Retrieval ◽  
Speckle Field

Shape and deformation measurements of 3D objects using volume speckle field and phase retrieval

2009 ◽  
Vol 34 (10) ◽  
pp. 1522 ◽  
Author(s):  
Arun Anand ◽  
Vani K Chhaniwal ◽  
Percival Almoro ◽  
Giancarlo Pedrini ◽  
Wolfgang Osten
Keyword(s):  
Phase Retrieval ◽  
Speckle Field ◽  
3D Objects ◽  
Deformation Measurements

A Magnetic Spectrometer for a Scanning Transmission Electron Microscope

1974 ◽  
Vol 32 ◽  
pp. 436-437
Author(s):  
A. Kosiara ◽  
J. W. Wiggins ◽  
M. Beer
Keyword(s):  
Scanning Transmission Electron Microscope ◽  
Magnetic Spectrometer ◽  
Fringe Field ◽  
Curvature Radius ◽  
Magnetic Pole ◽  
Quadrupole Field ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Under Construction ◽  
Image Position

A magnetic spectrometer to be attached to the Johns Hopkins S. T. E. M. is under construction. Its main purpose will be to investigate electron interactions with biological molecules in the energy range of 40 KeV to 100 KeV. The spectrometer is of the type described by Kerwin and by Crewe Its magnetic pole boundary is given by the equationwhere R is the electron curvature radius. In our case, R = 15 cm. The electron beam will be deflected by an angle of 90°. The distance between the electron source and the pole boundary will be 30 cm. A linear fringe field will be generated by a quadrupole field arrangement. This is accomplished by a grounded mirror plate and a 45° taper of the magnetic pole.

Quantitative analysis by reconstruction of HREM focal series

1994 ◽  
Vol 52 ◽  
pp. 740-741
Author(s):  
W. Coene ◽  
A. Thust ◽  
M. Op de Beeck ◽  
D. Van Dyck
Keyword(s):  
Phase Retrieval ◽  
Image Plane ◽  
Initial Guess ◽  
Recursive Least Squares ◽  
Objective Lens ◽  
Electron Wave ◽  
Electron Sources ◽  
Original Algorithm ◽  
Coherent Field ◽  
Direct Interpretation

Compared to conventional electron sources, the use of a highly coherent field-emission gun (FEG) in TEM improves the information resolution considerably. A direct interpretation of this extra information, however, is hampered since amplitude and phase of the electron wave are scrambled in a complicated way upon transfer from the specimen exit plane through the objective lens towards the image plane. In order to make the additional high-resolution information interpretable, a phase retrieval procedure is applied, which yields the aberration-corrected electron wave from a focal series of HRTEM images (Coene et al, 1992).Kirkland (1984) tackled non-linear image reconstruction using a recursive least-squares formalism in which the electron wave is modified stepwise towards the solution which optimally matches the contrast features in the experimental through-focus series. The original algorithm suffers from two major drawbacks : first, the result depends strongly on the quality of the initial guess of the first step, second, the processing time is impractically high.

Limitations to the Spacing Effect

2005 ◽  
Vol 52 (4) ◽  
pp. 257-263 ◽  
Author(s):  
Peter P. J. L. Verkoeijen ◽  
Remy M. J. P. Rikers ◽  
Henk G. Schmidt
Keyword(s):  
Free Recall ◽  
Phase Retrieval ◽  
Incidental Learning ◽  
Factor Model ◽  
Recall Performance ◽  
Spacing Effect ◽  
Word List ◽  
Intentional Learning ◽  
Study Phase ◽  
Learning Condition

Abstract. The spacing effect refers to the finding that memory for repeated items improves when the interrepetition interval increases. To explain the spacing effect in free-recall tasks, a two-factor model has been put forward that combines mechanisms of contextual variability and study-phase retrieval (e.g., Raaijmakers, 2003 ; Verkoeijen, Rikers, & Schmidt, 2004 ). An important, yet untested, implication of this model is that free recall of repetitions should follow an inverted u-shaped relationship with interrepetition spacing. To demonstrate the suggested relationship an experiment was conducted. Participants studied a word list, consisting of items repeated at different interrepetition intervals, either under incidental or under intentional learning instructions. Subsequently, participants received a free-recall test. The results revealed an inverted u-shaped relationship between free recall and interrepetition spacing in both the incidental-learning condition and the intentional-learning condition. Moreover, for intentionally learned repetitions, the maximum free-recall performance was located at a longer interrepetition interval than for incidentally learned repetitions. These findings are interpreted in terms of the two-factor model of spacing effects in free-recall tasks.

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