Interdiffusion Kinetics in Mo/Si Multilayers,

Abstract

Mo/Si multilayers (ML's) are attractive for x-ray optics relatively high associated reflectivity. However, the reflectivity is known to decrease with the formation of diffuse interlayer regions resulting from interdiffusion at the Mo-Si interfaces 1-2. Most of the previous studies have reported interdiffusion coefficients 1-5 and effective activation energies 2-4 over a range of temperature assuming that the interdiffusion coefficient is invariant with annealing time. At temperatures of 560-580 deg C, hexagonal molybdenum-disilicide (h-MoSi2) grows with a square root time dependence at the Mo-Si interface 6. This suggests diffusion-limited growth with a time-invariant interdiffusion coefficient. However, at temperatures of 300-400 deg C, the interlayer structure is known to change with annealing time from amorphous to crystalline 1-3, suggesting the possibility that the rate-controlling mechanism(s) for interdiffusion may also change with annealing time and/or temperature. Therefore, it is the objective of this study to perform a series of annealing treatments of Mo/Si ML's at temperatures lower than those previously reported to determine the Mo-Si interdiffusion kinetics as a function of time.

Document Details

Document Type
Technical Report
Publication Date
Mar 05, 1992
Accession Number
ADP008058

Entities

People

  • D.g. Stearns
  • M.a. Viliardos
  • M.e. Kassner
  • R.s. Rosen
  • S.p. Vernon

Organizations

  • Lawrence Livermore National Laboratory

Tags

DTIC Thesaurus Topics

  • Annealing
  • Coefficients
  • Diffusion
  • Energy
  • Heat Of Activation
  • Kinetics
  • Molybdenum
  • Optics
  • Physics
  • Reflectivity
  • Square Roots
  • Time Dependence
  • X Ray Optics
  • X Rays

Fields of Study

  • Materials science

Readers

  • Combustion science or combustion engineering.
  • Powder metallurgy of Titanium alloys.
  • Pulsed Power and Plasma Physics.