Optimization of Multi-Layered Thin Films for Minimizing Resistive Losses in Acoustic Resonators

Most NEMS devices use several metals, each serving its own function, such as electrical conductivity or stiffness. As those devices are mostly made of multiple layers, the electrical current must pass through several layers of metals that can be dissimilar. At the interfaces, a specific kind of resistance is found: contact resistance. The objective of this project is to measure and characterise the contact resistance between two metallic layers. Previous projects focused on DC structures whereas this one aims to observe whether previous characterisation works for a RF resonator or if the system is affected by the metal interface. Multiple combination of interfaces between different configurations of metals and surface treatments will be evaluated to better characterise contact resistance. This characterisation will lead to optimised fabrication process intended to minimise contact resistance and allowing production of better resonators. As the presence of contact resistance lowers the efficiency due to resistive losses.