High efficiency embedded decoupling capacitors for MCM applications

In this paper, RF characterization results of decoupling capacitors embedded in high resistivity silicon (HRS) substrate are reported. First, an innovative 3-D architecture suitable for silicon processes is decribed. Then, RF characterization results are analyzed based on capacitance values as well as ESR (estimated serial resistance) and ESL (estimated serial inductance) extraction. Results clearly show that devices reach a very low level of impedance together with low parasitic inductance in millimeter wave domain. A predictive electrical model composed of a cascade of T elements is derived from measurements and optimised to figure-out the distributed nature of the capacitance. Correlations between measurements and simulation data are found satisfactory.