Mitigation of tensile failure in released nanoporous metal microstructures via thermal treatment

The authors have developed a method to fabricate released microstructures of nanoporous Au (np-Au) by dealloying a Au-Ag alloy film patterned over a sacrificial Al layer. Doubly clamped bridges fail during dealloying owing to large tensile stresses induced during the dealloying process. Thermal treatments of released microstructures prior to dealloying generate sufficient compressive stress to induce plastic buckling. This buckling compensates the tensile stresses generated during the dealloying process, thus mitigating fracture of the np-Au. (c) 2006 American Institute of Physics.