Design of Electromagnetic Bandgap Structures in Glass Interposers Based on Dispersion Analysis for Signal and Power Integrity Improvement

This article proposes dispersion analysis for an efficient design of electromagnetic bandgap (EBG) structures in glass interposers to suppress power/ground noise coupling. The proposed method considered design parameters such as patch, through glass via (TGV), and defected structure which can be efficiently realized in glass interposers without additional fabrication steps. The unit cell of the EBG structure is modeled into transmission lines for an efficient dispersion analysis to estimate the power/ground noise suppression band. Impacts of capacitance associated with the patch, inductance of TGVs, and defected structure on the noise suppression bands are characterized for an efficient bandgap design. Various test vehicles are fabricated and measured to validate the proposed design methodology based on the dispersion analysis. The measured results showed good correlation with estimated noise suppression bandgaps which verifies the proposed design methodology based on dispersion analysis. The proposed method is further applied to design an EBG structure including multiple noise suppression bands for broadband noise suppression. The proposed design is validated using the 3-dimensional electromagnetic simulation. Effectiveness of the proposed EBG structure in the glass interposer on signal and power integrity is verified by analyzing noise propagation in the power delivery network and coupling to the TGV channel.