用侧向力显微镜对力/电/热耦合作用下金表面力学行为的研究

对微构件力/电/热等多域场下力学行为的研究有着重要的意义,利用原子力显微镜采用纳米压痕法对样品金在力-电-热耦合作用下的表面力学性能进行了研究,实验表明在压痕过程中,无论在无电场作用下还是有电场作用下,压痕周围的金属由于挤压形成了凸起,从扫描得到的形貌图中可以明显的看出,压痕周围的亮区为材料被挤出的区域.此外,在外加直流电场作用下,随电流的增大,硬度值有增大的趋势,而残余压痕和弹性模量都呈现减小的趋势.

Au surface mechanical behavior research with electro-thermo-mechanical coupled action using atomic force microscope

The mechanics problems can drastically compromise device performance and reliability. To solve these problems, there is a need to develop a fundamental understanding of mechanical behaviors of microstructures in MEMS. Au surface mechanical behavior is studied with electro-thermo-mechanical coupled action by using atomic force microscope. The experimental results show that some pile-ups of the metal around caused by indention were formed no matter whether the external electric field or not was applied in the process of the indention, in other words, the bright area around the indention hole which can be evidently seen from the scanned topographical image indicates the one where the materials were pushed out. Moreover, when the DC external electric field is applied, the hardness value of the tested sample presents an increase trend with the increment of electric current, but a decrease trend for the residue area and the elastic modulus.