Evaluation of high frequency characteristics of ALIVH substrate for 60 GHz RF modules

High frequency characteristics of any layer interstitial via hole (ALIVH) substrate have been evaluated for an application to the RF modules on 60GHz. A dielectric constant and loss tangent up to 60GHz was measured using strip line resonator designed on the ALIVH substrate. Measured dielectric constant 3.85-3.47 and loss tangent of 0.032-0.043 were almost constant from 2.5GHz to 60GHz. Equivalent lumped component circuit of via hole was modeled from measurement of frequency of strip line resonator with via hole. T-type LC circuit was employed for the circuit. The evaluated inductance was 0.090-0.128 nH and capacitance was 0.129-0.195 pF. It was confirmed that the high frequency characteristics of ALIVH were sufficient for the application to RF module and 3D SiP with no critical degradation.