关键词: 先进封装, 玻璃通孔, 信号完整性, 串扰抑制, 虚拟同轴结构

Abstract: As advanced packaging technologies evolve toward 3D high-density integration, glass substrates have become the preferred carrier for millimeter-wave applications due to their superior high-frequency electrical performance. However, because glass lacks the inherent shielding effect found in semiconductor substrates, high-density through-glass via (TGV) arrays face severe far-end crosstalk challenges. To address this issue, this study conducts an analysis of electromagnetic coupling mechanisms and investigates suppression techniques. The electric field distribution characteristics between glass and silicon substrates were compared using full-wave electromagnetic simulation, revealing the crosstalk mechanism attributed to unconstrained electric field radiation in the fully insulating medium. A virtual coaxial shielding structure based on a hexagonal ground via array was proposed. By constructing a Faraday cage to truncate the electric field propagation path, the array layout was optimized through parametric analysis. The proposed structure was comprehensively verified in both frequency and time domains under a multi-aggressor worst-case scenario. Simulation results demonstrate that the optimized shielding structure suppresses the power sum crosstalk (PSXT) to below 40 dB within the 100 GHz frequency band. In 100 Gbit/s high-speed signal transmission tests, the eye diagram of the victim channel remains clearly open, and timing jitter is effectively suppressed. This design significantly enhances the signal integrity of glass-based interconnects and is suitable for 3D integrated packaging in millimeter-wave applications.

Key words: advanced packaging, through-glass via, signal integrity, crosstalk suppression, virtual coaxial structure