Dopant diffusion in SM1-xGex thin films: Effect of epitaxial stress

A. Portavoce, I. Berbezier, A. Ronda, P. Gas, J. S. Christensen, A. Yu Kuznetsov, B. C. Svensson, J. Philibert, D. Beke

Research output: Contribution to journalArticle


We have investigated the lattice diffusion of B and Sb by means of molecular beam epitaxy in Si1-xGex (x < 0.2) layers grown on Si(001) substrate. Using Si1-xGex relaxed buffers we were able to differentiate the chemical effect (change in the Ge composition) as opposite to the biaxial stress effect (due to the epitaxy on Si) on dopant diffusion. B diffusion follows a behavior opposite to Sb diffusion versus Ge composition and biaxial stress. These results are explained in view of the difference of diffusion mechanism between B (interstitials) and Sb (vacancies). We also show that dopant diffusion follows contrasting behaviors under biaxial pressure and hydrostatic pressure, and that the activation volume of dopant diffusion is of opposite sign for biaxial pressure and for hydrostatic pressure. This is explained using a formalism based on the extra work done by the system for diffusion under pressure, concluding that for biaxial stress the activation volume depends mainly on the relaxation volume linked to the defect formation.

Original languageEnglish
Pages (from-to)135-142
Number of pages8
JournalDefect and Diffusion Forum
Publication statusPublished - 2006


  • B
  • Biaxial stress
  • Diffusion
  • Sb
  • SiGe

ASJC Scopus subject areas

  • Radiation
  • Materials Science(all)
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Dopant diffusion in SM<sub>1-x</sub>Ge<sub>x</sub> thin films: Effect of epitaxial stress'. Together they form a unique fingerprint.

  • Cite this

    Portavoce, A., Berbezier, I., Ronda, A., Gas, P., Christensen, J. S., Kuznetsov, A. Y., Svensson, B. C., Philibert, J., & Beke, D. (2006). Dopant diffusion in SM1-xGex thin films: Effect of epitaxial stress. Defect and Diffusion Forum, 249, 135-142.