基于理想因子退化的双极晶体管贮存寿命评估

Bipolar-transistor Storage Lifetime Assessment Based on Ideality Factor Degradation

提出了用理想因子n作为表征,对双极晶体管的贮存寿命进行评估的新方法。以某型双极晶体管为研究对象,进行了3组不同温、湿度恒定应力的加速退化试验,分析了随试验时间的增加双极晶体管样品的性能参数退化的原因。通过设定失效判据,利用晶体管样品在小电流情况下PN结的理想因子的退化趋势外推出双极晶体管的贮存寿命,并与通过反向漏电流的退化趋势预测得到的贮存寿命结果进行了对比。结果证明,晶体管PN结的理想因子退化也可以作为晶体管贮存寿命的一种表征,从而对晶体管的贮存可靠性进行评估。

A new method is proposed,which uses the ideality factor n as characterization to assess the storage lifetime of bipolar transistors.Choosing one bipolar transistors as the study object,three group ac-celerating degradation tests are conducted in the different temperature-humidity constant stresses.The re-search analyzed why the performance parameters of transistor samples degraded with the test time passing. By setting the failure criterion,the storage lifetime was extrapolated from the degradation trend of ideality factor PN junction in the small current,which was compared with that from the reverse leakage current. The findings prove the ideality factor PN junction can be taken as a characterization to evaluate the tran-sistor storage reliability.