Strain-induced wrinkling on SiGe free standing film

This study reports both experimental and theoretical investigation on the strain-induced wrinkling on Si1-xGex/Si free standing film. Clear periodical pattern is observed and attributed to the strain relaxation of the SiGe film. With increasing lateral length of the film, both wavelength and amplitude increase. Nonlinear Von Karman plate theory is employed to model the structure. From the analysis, it shows that the formation of the wrinkling pattern is a trade-off between bending energy and stretching energy. Based on the modeling, it is found that wavelength decreased with increasing Ge content, while vice versa for the amplitude. (c) 2006 American Institute of Physics.