Three dimensional strain distribution of wrinkled silicon nanomembranes fabricated by rolling-transfer technique

This paper introduces a simple transfer technique named as rolling-transfer technology to transfer Si nanomembranes to pre-stressed elastomers with nearly 100% transfer efficiency. When transferred onto the elastomeric substrate, wave-like wrinkled Si nanomembranes with uniform periodicity and amplitude are formed. The three dimensional (3-D) strain distribution of the wrinkled Si nanomembranes has been investigated in detail through the micro-Raman mapping using two excited laser wavelengths. The sinusoidal bulking geometry of Si nanomembrane results in a periodical strain alternation along x direction, while a homogenous strain distribution in y direction. The inhomogeneous strain distribution along z direction can be interpreted with the physical model considering the shift of the neutral mechanical plane, which is qualitatively determined by the Von Karman elastic nonlinear plate theory, including the bending effect and the shear forces existing at the Si nanomembrane/elastomeric substrate interface. (C) 2013 AIP Publishing LLC.