Equivalent Lumped Elements of DC-Biased Thin Film Microstrip Line in MMICs

This letter investigates the equivalent lumped elements of the thin film microstrip line (TFML) with different DC-bias voltages for the first time. The wide-band frequency-dependent characteristic impedance Z
_o
(f) and equivalent lumped elements such as R(f), L(f), G(f), and C(f) are accurately characterized for DC-biased TFML on a 20-m thick low dielectric constant (K) polyimide up to 50 GHz. The experimental results shows the DC-biased TFML can be extensively applied to the voltage-controlled passive and active integrated circuits.