板上驱动封装LED的电源IC失效分析  

Failure Analysis of Power Supply IC of LED with Driver-on-Board Package

作　　者：梁为庆 梁胜华 邬晶 周升威 黄家辉 林凯旋 邱岳 潘海龙 方方 LIANG Weiqing;LIANG Shenghua;WU Jing;ZHOU Shengwei;HUANG Jiahui;LIN Kaixuan;QIU Yue;PAN Hailong;FANG Fang(Department of Failure Analysis,Gold Medal Analytical&Testing Group,Guangzhou 511300,China)

机构地区：[1]广东金鉴实验室科技有限公司失效分析部,广州511300

出　　处：《电子与封装》2023年第10期21-25,共5页Electronics & Packaging

基　　金：第三代半导体氮化镓和碳化硅芯片和器件失效分析实验室资助项目(201901002)。

摘　　要：通过基础电性测试确认了板上驱动(DOB)封装LED光源的失效现象,通过X射线无损探测内部的结构,得到了基本电路结构原理图。分别对LED光源电路上的各个分立部分做示波器测试,确认了失效部位为电源IC。通过物理开封并结合扫描电子显微镜(SEM)、聚焦离子束显微镜(FIB-SEM)和能谱仪(EDS)测试,分析出该LED光源亮度下降的根本原因是电源IC异常。而该电源IC失效的原因为Fe元素残留与污染引发蚀刻异常,含Fe元素异物镶嵌在芯片内部,导致芯片内部蚀刻线路异常,造成内部功能单元失效,最终使IC功能偏离设计,局部或全部失效。The failure phenomenon of the LED light source with the driver-on-board(DOB)package is confirmed by basic electrical testing,and then the basic circuit structure schematic is obtained by X-ray non-destructive testing of the internal structure.Oscilloscope test is carried out on each discrete part of the LED light source circuit respectively,and the failure part is confirmed to be the power supply IC.Through physical opening of the package and combining with scanning electron microscope(SEM),focused ion beam-scanning electron microscope(FIB-SEM)and energy dispersive spectrometer(EDS)tests,it is analyzed that the root cause of the decrease in the brightness of the LED light source is the abnormal power supply IC.The reason for the failure of the power supply IC is that the Fe element residue and contamination trigger etching abnormality,and the Fe element-containing foreign matter is embedded inside the chip,leading to the abnormality of the etching line inside the chip,which results in the failure of the internal functional unit.Ultimately,the function of the IC is deviated from the design,and the IC partially or completely fails.

关 键 词：电源IC 板上驱动(DOB)封装LED 亮度下降 失效分析 

分 类 号：TN407[电子电信—微电子学与固体电子学]