Relaxation of mechanical stresses in bending of silicon wafers

Mechanical stress in the surface layers of silicon wafers subjected to a bending mode of central symmetry is investigated by Raman spectroscopy. An original setup for bending wafers makes it possible to simultaneously take optical measurements on the stretched and compressed sides of silicon wafers. On the stretched and compressed sides of the silicon wafers used in this work, the mechanical stress produces an elastic deformation of 0.42% and 0.18%, respectively.