Electromagnetic Radiation in the Range of GHz of Integrated Circuit Package with Heat Sink

With the increase of operating frequency of electronic devices, electromagnetic interference (EMI) radiation in the 20 GHz and higher frequency is becoming an increasingly difficult problem to solve, especially in the integrated circuit (IC) package with heat sink where the radiation from the chip will leak out through the gap between the heat sink and the ground plane of PCB. In this paper, the electromagnetic radiation mechanism of the package with heat sink in the frequency range up to 40 GHz is proposed from plenty of full-wave simulations using different absorbing materials, which is beneficial to the selection of package structural parameters and the suppression of radiation. According to the proposed mechanism, the methods to improve the EMI radiation suppression effect in the frequency range from 20 GHz to 30 GHz are designed.