Tensile behavior of free-standing gold films

A method for tensile testing thin gold films is presented. Free-standing tensile specimens were prepared by evaporating 0.8 mu m of gold onto a patterned oxidized silicon wafer. Using common microelectronic fabrication techniques, free-standing thin film specimens were produced that span rectangular windows in the wafer. The wafer was diced into individual tensile specimens composed of a thin film surrounded by a silicon frame. The final step before testing was to cleave the silicon frame so that the load was completely carried by the metal film. The ultimate tensile strength of the films was found to be approximately 150% greater than that of annealed bulk gold. In contrast, the measured elastic modulus for the thin film specimens was approximately the same as that documented for bulk gold.