Design and Analysis of CMOS-Based Terahertz Integrated Circuits by Causal Fractional-Order RLGC Transmission Line Model

A causal and compact fractional-order model is developed for complementary metal-oxide-semiconductor (CMOS) on-chip transmission line (T-line) at Terahertz (THz) frequencies. With consideration of the loss from frequency-dependent dispersion and nonquasi-static effects at THz, good agreement of characteristic impedance is observed between the proposed fractional-order model and the measurement up to 110 GHz, while traditional integer-order model can only match up to 10 GHz. The developed fractional-order model is further deployed in the design and analysis of CMOS-based THz integrated circuits that utilize T-line, such as standing-wave oscillator, which has significantly improved accuracy with causality.