摘要
柔性基板具有机械柔韧性和高密度互连的特点,现采用柔性基板来实现封装结构的也越来越多。柔性基板由于其机械弯曲引起的信号完整性问题和电磁干扰问题是柔性基板应用于高速高密电子封装的重要制约因素。针对该问题,应用三维仿真分析方法,分别从频域和时域研究了柔性基板在不同弯曲半径下的信号完整性与电磁干扰性的问题。仿真结果显示,弯曲半径增加一倍,插入损耗减小约0.9 dB,回波损耗减小约2 dB,电场辐射越弱,眼图的上升时间退化越小;即柔性基板弯曲半径越大,高速信号的传输质量越好。该结果为使用柔性基板实现三维高速高密封装提供理论依据。
Flexible substrate has mechanical flexibility to realize high density interconnection,and is now widely used in packaging structures.The signal integrity（SI） problems and electromagnetic interference（EMI） caused by the mechanical bending of flexible substrate restricted its use to a large extent.To settle this problem,3D simulation analysis is adopted to compare SI characteristics and EMI of flexible substrates with different bending radiuses both in frequency and time domains.The simulation results show that when bending radius doubles,insertion loss would reduce by 0.9 dB,return loss would reduce by 2 dB,electric field radiation would become weaker,and the rise time of eye diagram would display smaller degradation.In other words,the bending radius of flexible substrate is bigger,the transmission performance of signal is better.The result provides the theory basis for the use of flexible substrates in 3D high speed and high density packages.
出处
《科学技术与工程》
北大核心
2012年第12期2820-2824,共5页
Science Technology and Engineering
关键词
电子技术
信号完整性
三维仿真
柔性基板
electronic technology signal integrity 3D simulation flexible substrate
