Special issue on "Ten Years of Diffusion in Silicon",
Defect and Diffusion Forum 153-155, 1-10 (1998).
Pressure and Stress Effects on Diffusion in Si
Michael J. Aziz*
Division of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138
Keywords: thermodynamics, diffusion mechanism, nonhydrostatic stress, biaxial stress, dopant diffusion, self
diffusion, silicon, germanium, antimony, boron, arsenic.
The thermodynamics of diffusion under hydrostatic pressure and nonhydrostatic stress is
presented for single crystals free of extended defects. The thermodynamic relationships obtained
permit the direct comparison of hydrostatic and biaxial stress experiments and of atomistic calculations
under hydrostatic stress for any proposed mechanism. Atomistic calculations of the volume changes
upon point defect formation and migration, and experiments on the effects of pressure and stress on
the diffusivity, are reviewed. For Sb in Si, using as input the results of ab initio calculations of the
effect of hydrostatic pressure on diffusion by the vacancy mechanism, the thermodynamic
relationships successfully account for the measured effect of biaxial stress on diffusion with no free
parameters. For other cases, missing parameters are enumerated and experimental and calculational