AN INVESTIGATION OF CRYSTAL IMPERFECTIONS BY X-RAY DIFFRACTION

Abstract

All sections of the Si crystal showed a complex history of dislocation movement. Dislocation densities varied with distance from the crystal seed from 1000 to 100,000 lines/sq. cm. Interference of dislocations belonging to 2 or more slip systems gives rise to tangles. Several other reactions between individual dislocations were analyzed. X-ray topographs were made of Ge crystals in the form of tapering wedges to study (1) the contrast of images as a function of thickness, (2) the modulation of intensity of diffracted beams as a function of thickness, and (3) the effect of surface irregularities. Crystals of InSb were examined with dislocation densities ranging from about zero to 10,000 lines sq/cm. Progress is reported in heat-treating, etching, and handling of LiF. X-ray topographs of quartz show localized regions of enhanced reflecting power. Work was continued on extending and developing a basic theory of refraction of energy flow and a new approach to the diffraction theory of a distorted crystal.

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1961
Accession Number
AD0255047

Entities

People

  • Andrew R. Lang

Organizations

  • University of Bristol

Tags

DTIC Thesaurus Topics

  • Contrast
  • Diffraction
  • Dislocations
  • Intensity
  • Modulation
  • Refraction
  • Thickness
  • Wave Phenomena
  • X Rays
  • X-Ray Diffraction

Readers

  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.
  • Semiconductor Device Technology