X-ray diffraction (XRD) is an effective non-destructive tool for identifying solid crystalline samples. XRD analysis provides information about structure, phases, crystal orientations and other structural features; these includes mean grain size, stress, lattice errors and degree of crystallization. X-ray diffraction peaks are consequence of diffracted monochromatic X-ray’s constructive interference from different lattice planes with different angles. The intensity of peaks are determined by the orientations of atoms in the crystal lattice. The X-ray diffraction pattern is a samples finger print, the periodic atomic arrangements in a sample. X-ray diffraction patterns are identified by comparing them with ICDD-standard database patterns.

Main Applications of XRD Analysis

  • XRD Uses
    • Phase detection, solid and crystalline samples
    • Phase ratio relations from a sample with many phases (Rietweld analysis)
    • 1-crystalline matter orientation solving

    Typical samples

    • Process products in mining industry
    • Definition of clays found in joints in underground cavaties, especially ratio between clay minerals in swallowing clays
    • Mineral identification
    • Mineral ratios for samples with many phases
    • Asbestos
Ideal Uses
  • Phase identification for a large variety of bulk and thin-film samples
  • Detecting crystalline minority phases (at concentrations greater than ~1%)
  • Determining crystallite size for polycrystalline films and materials
  • Determining percentage of material in crystalline form versus amorphous
  • Measuring sub-milligram loose powder or dried solution samples for phase identification
  • Analyzing films as thin as 50 angstroms for texture and phase behaviors
  • Determining strain and composition in epitaxial thin films
  • Determining surface offcut in single crystal materials
  • Measuring residual stress in bulk metals and ceramics
Techincal Specifications
  • Signal Detected: Diffracted x-rays
  • Elements Detected: All elements, assuming they are present in a crystalline matrix
  • Detection Limits: Quantitative multiphase analysis: ~1%
  • External standard quantitative analysis: ~0.1%
  • Special quantitative analysis (quartz, polymorphs): ~0.02%
  • Minimum film thickness for phase identification: ~20 Angstroms
  • Depth Resolution: Adjustable sampling depth between ~20 Angstroms to ~30 microns, depending on material properties and x-ray incidence angles
  • Imaging/Mapping: None
  • Lateral Resolution/Probe Size: Point focus: 0.1mm to 0.5mm; Line focus 2mm to 12 mm
Strengths
  • Nondestructive
  • Quantitative measurement of phase contents and texture orientation
  • Minimal or no sample preparation requirements
  • Ambient conditions for all analysis
Limitations
  • Cannot identify amorphous materials
  • No depth profile information
  • Minimum spot size of ~50um
Applications
  • Aerospace
  • Automotive
  • Medical Implants
  • Compound Semiconductor
  • Data Storage
  • Displays
  • Electronics
  • Industrial Products
  • Lighting
  • Pharmaceutical
  • Photonics
  • Polymer
  • Semiconductor
  • Solar Photovoltaics