Effectiveness of bubble structure in contact damage reduction of Au film

Au films have been utilized widely for electrical connectors and devices. The film may be damaged due to repeated contact sliding which may ultimately lead to failure of the electrical system. In this work, the effect of bubble structure on the contact damage characteristics of Au film was compared to that of a smooth film to understand the wear mechanism of thin Au films with the aim to improve its durability. Nano-scratch tests as well as sliding wear experiments were performed using smooth and bubble-structured Au film specimens. It was found that the bubble-structured film was more durable with respect to contact damage. The reason for the increased durability was attributed to the frictional energy dissipation function of the bubble structure. ► Contact damage properties of smooth and bubble-structured Au films were investigated. ► Smooth and bubble-structured Au films were deposited on Si by magnetron sputtering. ► Bubble-structured Au film was significantly more wear resistant than the smooth film. ► Friction coefficients of both films were similar and ranged between 0.26 and 0.53. ► Bubble-structure was beneficial for frictional energy dissipation and damping.