Impact of the Ball Grid Array Connection Failures on Signal Integrity

Ball grid arrays (BGA) are widely used in micro assemblies to provide both the mechanical connection between the chip substrate and the circuit board, and the electrical connection between the chip circuit and the peripheral matching circuit. Connection failures of a ball grid array may result in deterioration of signal integrity and low communication quality. In the present work, the impact of a degraded ball grid array connection on high-frequency characteristics was studied. A 3-D electromagnetic field model and an equivalent circuit model of a degraded ball grid array were developed. The electrical performance of the degraded ball grid array was analyzed and simulated. It was found that the 3-D electromagnetic field model results were in good agreements with the predicted behaviors from equivalent circuit model simulations. The characteristics of the ball grid array for different degradation levels were then compared and analyzed. This research serves to provide a better understanding of the effects of ball grid array deterioration on signal performance for application in fault detection strategies for electronic systems.