Silicon carbide amorphization by electron irradiation

PDF Version Also Available for Download.

Description

Observations made more than ten years ago showed that SiC could be made amorphous at cryogenic temperatures by in-situ 300kV electron irradiation. However, high voltage electron microscope (HVEM) results indicate a threshold voltage of 725 kV for amorphization of SiC at 140 K. In addition, a recent review exposes the considerable uncertainty in the literature regarding displacement energies for SiC. Therefore, further experiments have been performed in a Philips CM30 (LaB{sub 6} cathode) with a Gatan double-tilt cooling holder in an attempt to determine the threshold voltage for amorphization at {approximately} 140 K. Sintered {alpha}-SiC (defected 6H polytype), beam direction ... continued below

Physical Description

4 p.

Creation Information

Bentley, J. February 1, 1998.

Context

This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by UNT Libraries Government Documents Department to Digital Library, a digital repository hosted by the UNT Libraries. More information about this article can be viewed below.

Who

People and organizations associated with either the creation of this article or its content.

Author

Sponsor

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this article. Follow the links below to find similar items on the Digital Library.

Description

Observations made more than ten years ago showed that SiC could be made amorphous at cryogenic temperatures by in-situ 300kV electron irradiation. However, high voltage electron microscope (HVEM) results indicate a threshold voltage of 725 kV for amorphization of SiC at 140 K. In addition, a recent review exposes the considerable uncertainty in the literature regarding displacement energies for SiC. Therefore, further experiments have been performed in a Philips CM30 (LaB{sub 6} cathode) with a Gatan double-tilt cooling holder in an attempt to determine the threshold voltage for amorphization at {approximately} 140 K. Sintered {alpha}-SiC (defected 6H polytype), beam direction B = <11{bar 2}0>, and probes containing {approximately} 75 nA in {approximately} 0.5 {micro}m, were used. Amorphization occurred in <10 min at 300 kV and after {approximately} 60 min at 180 kV; visible darkening occurred at lower voltages and doses. Similar behavior occurred for B = [0001]. The critical dose for amorphization was measured as a function of accelerating voltage. Probe current profiles were measured by post-specimen scanning (CM30 SCIM mode with 100 {micro}m diameter Gatan STEM detector) images of the focused probes positioned in a hole, and probe currents were measured from the exposure time, which had previously been calibrated with a Faraday cup.

Physical Description

4 p.

Notes

INIS; OSTI as DE98004938

Source

  • Microscopy and microanalysis 1998, Atlanta, GA (United States), 12-16 Jul 1998

Language

Item Type

Identifier

Unique identifying numbers for this article in the Digital Library or other systems.

  • Other: DE98004938
  • Report No.: ORNL/CP--96799
  • Report No.: CONF-980713--
  • Grant Number: AC05-96OR22464
  • Office of Scientific & Technical Information Report Number: 650389
  • Archival Resource Key: ark:/67531/metadc704223

Collections

This article is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this article?

When

Dates and time periods associated with this article.

Creation Date

  • February 1, 1998

Added to The UNT Digital Library

  • Sept. 12, 2015, 6:31 a.m.

Description Last Updated

  • Jan. 21, 2016, 12:14 p.m.

Usage Statistics

When was this article last used?

Yesterday: 0
Past 30 days: 0
Total Uses: 9

Interact With This Article

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

International Image Interoperability Framework

IIF Logo

We support the IIIF Presentation API

Bentley, J. Silicon carbide amorphization by electron irradiation, article, February 1, 1998; Tennessee. (digital.library.unt.edu/ark:/67531/metadc704223/: accessed October 21, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.