Interconnect processes and reliability for RF technology

High performance radio frequency (RF) technology is required for many communications applications, such as mobile phones. The interconnects for RF circuits are different from those for digital circuits in a number of ways, including thick wiring layers (>; 3 μm), extensive use of passive devices such as thin film resistors, metal-insulator-metal (MIM) capacitors, and inductors, and use of through-silicon vias (TSVs) for ground planes. As a result, there are a number of unique reliability challenges for these devices, including controlling stress in thick wiring layers and TSVs, and ensuring reliability of MIM capacitor dielectrics. In this paper, we will describe process optimization and reliability evaluation for interconnects in RF circuits.