脉冲方波作用下印制电路板互连系统的击穿特性

Breakdown on Interconnect System of Printed Circuit Board under Square Wave Pulse

通过脉冲直接注入法,研究了印制电路板(PCB)互连系统在脉冲方波作用下的击穿损伤特性,并根据试验结果对脉冲方波作用下的PCB互连系统进行了绝缘性能评价.性能评价中利用了试样的击穿行为符合威布尔分布模型的特点,通过统计分析方法,得到试样在不同电极间距以及注入脉冲宽度时的累积失效概率曲线.研究结果表明,当在PCB平行互连线间注入方波脉冲时,其线间击穿场强随线间距离的增大而减小,且变化趋势存在两个明显的阶段,同时击穿场强也随注入脉冲宽度的增大而减小.比较击穿前后的微观形貌特征和击穿场强的变化趋势发现,具有特定结构特征的PCB平行互连线间的击穿行为属于"固-气"复合介质的击穿,且绝缘强度不可恢复.另外,通过威布尔统计方法,对击穿数据进行分析处理,可以得到该类器件在不同状况下的累积失效率曲线,从而为该类器件在方波脉冲下的绝缘性能评价研究提供重要参考.

Electrical breakdown characteristics of interconnect system on printed circuit board （PCB） under square pulse are investigated with direct pulse injection. And the performance evaluation for the interconnect system insulation is carried out according to the experimental results. Following the fact that the breakdown behaviors agree with Weibull distribution, the curves of cumulative failure rate under the conditions of different insulation gap distances and different injection pulse widths are obtained by statistical analysis. It is indicated that as parallel interconnects on PCB are injected with square pulse, the breakdown field strength increases with the decreasing insulation distance, accompanied with two distinct phases; breakdown field strength also decreases with increasing injection pulse width. Compared with the breakdown characteristics and morphology before and after breakdown, the breakdown behavior between parallel interconnects on PCB is thought as ＂solid-gas＂ composite dielectric accompanied by an unrecoverable dielectric strength. The insulation failure rate curves of samples under different conditions are obtained by Weibull statistical methods to provide an important reference for the insulation performance evaluation of similar devices under the impact of square pulse.