Novel Multilayer Dipoles for Wireless Inter-/Intraconnects

A novel multi-metal-layer dipole antenna, in which some identical dipoles are deployed on different metal layers and effectively connected by the feeding and shorting vias, is proposed for wireless inter-/intraconnects. An accurate equivalent model is also presented for better understanding of its physical fundamentals. Simulations show that a six-layer dipole typically has a size reduction of 13.0% and a bandwidth enhancement of 35.3% compared with the corresponding one-layer dipole. An example chip carrying one- and six-layer dipoles was also fabricated through a 0.18-¿m mixed-mode process and on-wafer characterized with full two-port measurements. The experimental results show that further size reduction and bandwidth enhancement could be obtained due to the loadings of lossy vias in six-layer dipoles, and the transmission coefficients of multilayer dipoles could also be improved for the in-phase additive contributions of dipoles on different layers. The propagation mechanisms of wireless intraconnects were evaluated and discussed with the assistance of path-loss coefficient ¿, and it is revealed that the propagation is mostly through the surface waves when the dipole operate far below its resonant frequency, while the space-wave propagation would dominate when approaching the resonant frequency.