Production of optical tube array using sectional-uniform magnetic current LSA

Abstract In this paper, we demonstrate cases for actual short and open failures in FCB (Flip Chip Bonding) substrates by using novel non-destructive techniques, known as SSM (Scanning Super-conducting Quantum Interference Device Microscopy) and Terahertz TDR (Time Domain Reflectometry) which is able to pinpoint failure locations. In addition, the defect location and accuracy is verified by a NIR (Near Infra-red) imaging system which is also one of the commonly used non-destructive failure analysis tools, and good agreement was made.

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High-Resolution Backside GMR Magnetic Current Imaging on a Contour-Milled Globally Ultrathin Die

ISTFA 2014: Conference Proceedings from the 40th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2014p0023 ◽

2014 ◽

Author(s):

D. Vallett ◽

J. Gaudestad ◽

C. Richardson

Keyword(s):

Quantum Interference ◽

Flip Chip ◽

Milling Process ◽

Dramatic Improvement ◽

Superconducting Quantum Interference Device ◽

Density Peak ◽

Magnetic Current ◽

Gmr Sensors ◽

Silicon Thickness ◽

A Current

Abstract Magnetic current imaging (MCI) using superconducting quantum interference device (SQUID) and giant-magnetoresistive (GMR) sensors is an effective method for localizing defects and current paths [1]. The spatial resolution (and sensitivity) of MCI is improved significantly when the sensor is as close as possible to the current paths and associated magnetic fields of interest. This is accomplished in part by nondestructive removal of any intervening passive layers (e.g. silicon) in the sample. This paper will present a die backside contour-milling process resulting in an edge-to-edge remaining silicon thickness (RST) of < 5 microns, followed by a backside GMR-based MCI measurement performed directly on the ultra-thin silicon surface. The dramatic improvement in resolving current paths in an ESD protect circuit is shown as is nanometer scale resolution of a current density peak due to a power supply shortcircuit defect at the edge of a flip-chip packaged die.

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Magnetic Current Imaging Power Short Localization

ISTFA 2015: Conference Proceedings from the 41st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2015p0222 ◽

2015 ◽

Author(s):

J. Gaudestad ◽

F. Rusli ◽

A. Orozco ◽

M.C. Pun

Keyword(s):

Thermal Imaging ◽

Flip Chip ◽

Optical Microscope ◽

Fault Isolation ◽

Magnetic Current ◽

Multiple Fault ◽

Defect Location ◽

Isolation Techniques ◽

Chip Sample

Abstract A Flip Chip sample failed short between power and ground. The reference unit had 418Ω and the failed unit with the short had 16.4Ω. Multiple fault isolation techniques were used in an attempt to find the failure with thermal imaging and Magnetic Current Imaging being the only techniques capable of localizing the defect. To physically verify the defect location, the die was detached from the substrate and a die cracked was seen using a visible optical microscope.

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Magnetic Current Imaging Techniques: Comparative Case Studies

ISTFA 2004: Conference Proceedings from the 30th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2004p0029 ◽

2004 ◽

Author(s):

Olivier Crépel ◽

Philippe Descamps ◽

Patrick Poirier ◽

Romain Desplats ◽

Philippe Perdu ◽

...

Keyword(s):

Magnetic Field ◽

Integrated Circuits ◽

Case Studies ◽

Flip Chip ◽

Imaging Techniques ◽

Optimal Domain ◽

Magnetic Current ◽

Comparative Case Studies ◽

Current Flows

Abstract Magnetic field based techniques have shown great capabilities for investigation of current flows in integrated circuits (ICs). After reviewing the performances of SQUID, GMR (hard disk head technologies) and MTJ existing sensors, we will present results obtained on various case studies. This comparison will show the benefit of each approach according to each case study (packaged devices, flip-chip circuits, …). Finally we will discuss on the obtained results to classify current techniques, optimal domain of applications and advantages.

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Post-Hurricane Michael damage assessment using ADCIRC storm surge hindcast, image classification, and LiDAR

Shore & Beach ◽

10.34237/1008741 ◽

2019 ◽

pp. 3-14 ◽

Cited By ~ 1

Author(s):

Joshua Davis ◽

Diana Mitsova ◽

Tynon Briggs ◽

Tiffany Briggs

Keyword(s):

Wave Energy ◽

Field Studies ◽

Feedback Mechanism ◽

Water Velocity ◽

Airborne Lidar ◽

Storm Events ◽

Magnetic Current ◽

Coastal Mapping ◽

Electro Magnetic

Wave forcing from hurricanes, nor’easters, and energetic storms can cause erosion of the berm and beach face resulting in increased vulnerability of dunes and coastal infrastructure. LIDAR or other surveying techniques have quantified post-event morphology, but there is a lack of in situ hydrodynamic and morphodynamic measurements during extreme storm events. Two field studies were conducted in March 2018 and April 2019 at Bethany Beach, Delaware, where in situ hydrodynamic and morphodynamic measurements were made during a nor’easter (Nor’easter Riley) and an energetic storm (Easter Eve Storm). An array of sensors to measure water velocity, water depth, water elevation and bed elevation were mounted to scaffold pipes and deployed in a single cross-shore transect. Water velocity was measured using an electro-magnetic current meter while water and bed elevations were measured using an acoustic distance meter along with an algorithm to differentiate between the water and bed during swash processes. GPS profiles of the beach face were measured during every day-time low tide throughout the storm events. Both accretion and erosion were measured at different cross-shore positions and at different times during the storm events. Morphodynamic change along the back-beach was found to be related to berm erosion, suggesting an important morphologic feedback mechanism. Accumulated wave energy and wave energy flux per unit area between Nor’easter Riley and a recent mid-Atlantic hurricane (Hurricane Dorian) were calculated and compared. Coastal Observations: JALBTCX/NCMP emergency-response airborne Lidar coastal mapping & quick response data products for 2016/2017/2018 hurricane impact assessments

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Bianisotropic metasurfaces: physics and applications

Nanophotonics ◽

10.1515/nanoph-2017-0132 ◽

2018 ◽

Vol 7 (6) ◽

pp. 1069-1094 ◽

Cited By ~ 59

Author(s):

Viktar S. Asadchy ◽

Ana Díaz-Rubio ◽

Sergei A. Tretyakov

Keyword(s):

State Of The Art ◽

Surface Current ◽

Magnetic Surface ◽

Magnetic Polarization ◽

Research Directions ◽

Magnetic Current ◽

Asymmetric Reflection ◽

Composite Layers ◽

Electric And Magnetic Fields

AbstractMetasurfaces as optically thin composite layers can be modeled as electric and magnetic surface current sheets flowing in the layer volume in the metasurface plane. In the most general linear metasurface, the electric surface current can be induced by both incident electric and magnetic fields. Likewise, magnetic polarization and magnetic current can be induced also by external electric field. Metasurfaces which exhibit magnetoelectric coupling are called bianisotropic metasurfaces. In this review, we explain the role of bianisotropic properties in realizing various metasurface devices and overview the state-of-the-art of research in this field. Interestingly, engineered bianisotropic response is seen to be required for realization of many key field transformations, such as anomalous refraction, asymmetric reflection, polarization transformation, isolation, and more. Moreover, we summarize previously reported findings on uniform and gradient bianisotropic metasurfaces and envision novel and prospective research directions in this field.

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