Transmission-line based modeling for conformal shielding in advance system-in-package (SiP)

In order to efficiently eliminate the noise generated from high-speed integrated circuits, the conformal shielding technology is gradually utilized in advanced System-in-Package (SiP). In this paper, a prediction method based on the transmission-line theory is proposed for evaluating shielding effectiveness (SE) of conformal shielding on SiP. SE measurement of various coating materials is done and presented. By using 4-μm copper, the measured SE successfully demonstrates about 45 dB at the operating frequency of 1 GHz. The proposed model shows a good agreement compared with measured results from 0.01 GHz to 1 GHz.