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Title: Using the Line-VISAR to Study Multi-Dimensional and Meso-Scale Impact Phenomena.

Abstract

Abstract not provided.

Authors:
;  [1];  [1];  [1];  [1];  [1];
  1. Sandia National Laboratories, Albuquerque, NM
Publication Date:
Research Org.:
Sandia National Laboratories Albuquerque, NM; Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1147903
Report Number(s):
SAND2007-2948J
523299
DOE Contract Number:
DE-AC04-94AL85000
Resource Type:
Journal Article
Resource Relation:
Journal Name: International Journal of Impact Engineering; Related Information: Proposed for publication in International Journal of Impact Engineering.
Country of Publication:
United States
Language:
English

Citation Formats

Vogler, Tracy, Trott, Wayne, Reinhart, William D., Alexander, C. Scott, Furnish, Michael D., Knudson, Marcus D., and Chhabildas, Lalit C. Using the Line-VISAR to Study Multi-Dimensional and Meso-Scale Impact Phenomena.. United States: N. p., 2007. Web.
Vogler, Tracy, Trott, Wayne, Reinhart, William D., Alexander, C. Scott, Furnish, Michael D., Knudson, Marcus D., & Chhabildas, Lalit C. Using the Line-VISAR to Study Multi-Dimensional and Meso-Scale Impact Phenomena.. United States.
Vogler, Tracy, Trott, Wayne, Reinhart, William D., Alexander, C. Scott, Furnish, Michael D., Knudson, Marcus D., and Chhabildas, Lalit C. Tue . "Using the Line-VISAR to Study Multi-Dimensional and Meso-Scale Impact Phenomena.". United States. doi:.
@article{osti_1147903,
title = {Using the Line-VISAR to Study Multi-Dimensional and Meso-Scale Impact Phenomena.},
author = {Vogler, Tracy and Trott, Wayne and Reinhart, William D. and Alexander, C. Scott and Furnish, Michael D. and Knudson, Marcus D. and Chhabildas, Lalit C},
abstractNote = {Abstract not provided.},
doi = {},
journal = {International Journal of Impact Engineering},
number = ,
volume = ,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
  • Abstract not provided.
  • Recent advances in epitaxial growth have led to the growth of III-nitride devices on 2D layered h-BN. This advance has the potential for wafer-scale transfer to arbitrary substrates, which could improve the thermal management and would allow III-N devices to be used more flexibly in a broader range of applications. We report wafer scale exfoliation of a metal organic vapor phase epitaxy grown InGaN/GaN Multi Quantum Well (MQW) structure from a 5 nm thick h-BN layer that was grown on a 2-inch sapphire substrate. The weak van der Waals bonds between h-BN atomic layers break easily, allowing the MQW structure tomore » be mechanically lifted off from the sapphire substrate using a commercial adhesive tape. This results in the surface roughness of only 1.14 nm on the separated surface. Structural characterizations performed before and after the lift-off confirm the conservation of structural properties after lift-off. Cathodoluminescence at 454 nm was present before lift-off and 458 nm was present after. Electroluminescence near 450 nm from the lifted-off structure has also been observed. These results show that the high crystalline quality ultrathin h-BN serves as an effective sacrificial layer—it maintains performance, while also reducing the GaN buffer thickness and temperature ramps as compared to a conventional two-step growth method. These results support the use of h-BN as a low-tack sacrificial underlying layer for GaN-based device structures and demonstrate the feasibility of large area lift-off and transfer to any template, which is important for industrial scale production.« less
  • For this study synchrotron radiation micro-­tomography, a non-destructive three-dimensional imaging technique, is employed to investigate an entire microelectronic package with a cross-sectional area of 16 x 16 mm. Due to the synchrotron’s high flux and brightness the sample was imaged in just 3 minutes with an 8.7 μm spatial resolution.
  • Synchrotron radiation micro-tomography (SRµT) is a non-destructive three-dimensional (3D) imaging technique that offers high flux for fast data acquisition times with high spatial resolution. In the electronics industry there is serious interest in performing failure analysis on 3D microelectronic packages, many which contain multiple levels of high-density interconnections. Often in tomography there is a trade-off between image resolution and the volume of a sample that can be imaged. This inverse relationship limits the usefulness of conventional computed tomography (CT) systems since a microelectronic package is often large in cross sectional area 100-3,600 mm 2 , but has important features onmore » the micron scale. The micro-tomography beamline at the Advanced Light Source (ALS), in Berkeley, CA USA, has a setup which is adaptable and can be tailored to a sample's properties, i.e., density, thickness, etc., with a maximum allowable cross-section of 36 x 36 mm. This setup also has the option of being either monochromatic in the energy range ~7-43 keV or operating with maximum flux in white light mode using a polychromatic beam. Presented here are details of the experimental steps taken to image an entire 16 x 16 mm system within a package, in order to obtain 3D images of the system with a spatial resolution of 8.7 µm all within a scan time of less than 3 min. Also shown are results from packages scanned in different orientations and a sectioned package for higher resolution imaging. In contrast a conventional CT system would take hours to record data with potentially poorer resolution. Indeed, the ratio of field-of-view to throughput time is much higher when using the synchrotron radiation tomography setup. The description below of the experimental setup can be implemented and adapted for use with many other multi-materials.« less