基于HFSS的高速互连BGA焊点信号完整性仿真分析

Analysis of Signal Integrity of the High-speed Interconnects BGA Solder Joint Based on HFSS

基于HFSS软件建立了球栅阵列(Ball Grid Array:BGA)焊点模型,获取了焊点表面电场强度分布和回波损耗,分析了信号频率对电场强度分布的影响以及信号频率、焊点最大径向尺寸、焊盘直径和焊点高度对焊点回波损耗的影响;对9种不同参数水平组合的BGA焊点回波损耗进行了极差分析。结果表明:焊点内电场强度随频率增加而减小;回波损耗随信号频率升高和焊点最大径向尺寸增大而增大、随焊盘直径增大和焊点高度增高而减少;对信号完整性影响由大到小依次为:焊点高度、焊盘直径、频率和焊点最大径向尺寸。

The BGA solder joint simulation model was built by HFSS software, both of the electric field strength distribution and the return loss of BGA solder joints were obtained. The impacts of signal frequency on electric field strength distribution and the impacts of signal frequency, solder joint maximum radial size, pad diameter and solder joint height on return loss were also studied; the return loss range analysis of BGA solder joints which has 9 different process parameters＇ levels combinations was performed. Studying results show that the electric field strength decreases as signal frequency increased; The return loss increases as the signal frequency and the maximum radial size of the solder joint increased, and decreases as the pad diameter and the height of solder joint increased; The impact sequence of process parameters on signal integrity from high to low are the solder joint height, pad diameter, signal frequency and the solder joint maximum radial size.