Fundamental components of the IC packaging electromagnetic interference (EMI) analysis

The IC packaging EMC/SI/PI problems have been broadly attested. But IC packaging EMI was seldom addressed. Because the EMI emission by IC packagings is increasingly significant, in this paper, EMI behaviors are systematically studied. To fundamentally understand the radiation mechanism, radiated contributions from ground lids, vias, and traces of the packaging are investigated and modeled separately. It is seen that the packaging EMI has clearly low frequency and high frequency behaviors. The low frequency behavior is due to the Hertzian dipole effects of vias. The high frequency behavior is due to the radiation of excited cavity modes. Both theoretical analysis based on first principles and simulated results based on the numerical full wave solver are provided to find out critical impact factors to IC packaging EMI. This work provides basic modeling components for comprehensive radiation studies in the future. It directly benefits fundamental understandings and guidelines for the optimal design of the packaging EMI reduction.