Performance modeling and broadband characterization of chip-to-chip interconnects with rough surfaces

Planar copper interconnects suffer from surface roughness that results in their performance degradation. In this paper, we investigate the role of rough conductor surfaces on the electrical performance of chip-to-chip interconnects using 3D full wave simulation. Various interconnect performance metrics, such as delay, energy-delay product, bandwidth density, insertion loss and signal attenuation are evaluated over broadband frequencies. Our results show that rough conductor surfaces can significantly influence these metrics. In that, the maximum penalty on insertion loss, attenuation, delay, energy-delay product and bandwidth density is 50%, 86%, 3X, 3.7X and 28%, respectively. Finally, we report the computational overhead for simulating high-speed interconnects with rough surfaces.