A New CMOS Multilayer Electromagnetic Band-Gap Microstrip Line and Experimental Investigation of UWB Pulse Propagation

We report on the development of a new microstrip line and Its experimental results on ultra-wideband pulse propagation. The transmission line employs electromagnetic band-gap (EBG) structures and is implemented in the multilayer metal stack of a 0.25-mum CMOS process. The inductance and capacitance per unit length of the new microstrip line can be independently adjusted to achieve various slow-wave factors for different characteristic impedances by properly selecting the dimensions of the EBG cells, their respective locations, and the CMOS metal layers. Experimental time-domain investigation of the pulse propagation reveals an interesting phenomenon of pulse compression. This unique property of the new CMOS multilayer EBG microstrip line can be exploited to help generate pico-second pulse as well as to compensate for the loss and dispersion of transmission lines, hence effectively retaining or enhancing the pulse propagation characteristics in UWB impulse circuits.