Surface wrinkling of an elastic film: Effect of residual surface stress

The effect of residual surface compression on the surface evolution of solid thin films was analyzed. Analytical relation was derived among the apparent surface stress, the spatial frequency of the surface modulation, and the film thickness. Using this relationship, we calculated the dependence of the apparent surface stress on the film thickness from the experimental results of the polymer resist coated on glass slide. The magnitude of the apparent surface stress decreased with the reduction in the film thickness, and it approached a constant of 0.46 kN/m as the thickness of the films approached zero. The result is possibly applied to nanoimprint technology.