Lowering coupling noise between chips in System-in-Package (SiP) module using compartment shielding

SiP modules have been widely used in consumer electronic products. Many different functions are integrated in a SiP module, and these functions generate electromagnetic coupling interference between one another at different frequencies. In order to maintain high performance in all functions in a SiP module, it is necessary to prevent coupling electromagnetic interference (EMI) between adjacent electronic components. This paper presents a new spray coating technology for compartment shielding for SiP application. The first section of this paper introduces the process flow of spray coating for compartment shielding. Unlike traditional coating process, spray coating is more effective with higher performance. The second section of the paper is S.E. measurement results. A substrate pattern similar to a SiP system with a package size of 25.8 × 26.2 × 1.1 mm is designed. S.E. value is measured through VNA with a special socket we designed, and the impact of process variations is discussed. Finally, conclusions are given.