片式厚膜电阻器长期可靠性及失效模式研究  

Study on Long-term Reliability and Failure Mode of Thick Film Resistors

作　　者：张放 王波[1] 丁亭鑫 ZHANG Fang;WANG Bo;DING Tingxin(Zhongxing Telecommunication Equipment Corporation,Shenzhen 518057,China)

机构地区：[1]中兴通讯股份有限公司,广东深圳518057

出　　处：《电子工艺技术》2020年第2期118-121,共4页Electronics Process Technology

摘　　要：通过采用不同程度的高温高湿试验对片式厚膜电阻器长期可靠性及失效模式展开试验验证及研究分析。结果表明:片式厚膜电阻器在85℃,85%RH,10%RV,2000 h的试验条件下,水汽容易入侵片式厚膜电阻激光调阻切割槽处,在电阻内部形成并联电路,导致电阻的阻值下降,而在121℃,100%RH,0.21 MPa,10%RV的试验条件下,片式厚膜电阻器不仅会出现水汽入侵的情况,其G 1玻璃上还可能会发生Bi元素的析出或者迁移,导致电阻内部G 1玻璃的绝缘间隙变短甚至直接导通,电阻的阻值下降。此外,正确的三防涂覆工艺能够有效提高电阻在高温高湿的可靠性水平。但是,如果在三防涂覆工艺之前,器件及PCB已经受潮,那么三防涂覆工艺会降低片式厚膜电阻器的长期可靠性。The long-term reliability and failure mode of the thick film resistors under high temperature and high humidity are analyzed,tested and verifi ed by means of high temperature and high humidity test in different degrees.The results show that,under the test condition of 85℃85%RH,10%RV,2000 h,water vapor is easy to invade the thick fi lm resistance laser cutting groove,a parallel circuit is formed inside the resistance,which results in a decrease in the resistance value.Under the test conditions of 121℃,100%RH,0.21 MPa,10%RV,the thick fi lm resistor will not only have water vapor intrusion,but also the Bi element can be precipitated or migrated on the G 1 glass,which will cause the insulation gap of G 1 glass to become shorter or even directly conductive,resulting in a decrease in the resistance.In addition,the correct coating process can effectively improve the reliability level of the resistance under the condition of high temperatures and humidity.However,if the device and PCB are already moisture-driven prior to the coating process,the coating process will reduce the long-term reliability of the thick fi lm resistor.

关 键 词：厚膜电阻器 高温高湿 失效模式 长期可靠性 

分 类 号：TN60[电子电信—电路与系统]