Title :
Failure analysis of plastic packaged optocoupler light emitting diodes
Author :
Hwang, Nam ; Naidu, Priya Sarapna Rajoo ; Trigg, Alastair
Author_Institution :
Inst. of Microelectron., Singapore, Singapore
Abstract :
Failure mechanisms in plastic packaged optocouplers have been investigated. The high failure rate of the optocouplers, specifically the reverse bias leakage current of the light emitting diodes (LEDs), was found to be moisture-related. Using scanning electron microscopy coupled with energy dispersive X-ray microanalysis, a significant concentration of copper was detected on the surface of failed LEDs, possibly migrated from the copper leadframe. By applying infra-red photoemission microscopy it was found that bandgap emission was associated with the reverse leakage path in the area of the pn junction of the LEDs.
Keywords :
X-ray chemical analysis; copper; failure analysis; leakage currents; life testing; light emitting diodes; moisture; opto-isolators; photoelectron microscopy; plastic packaging; scanning electron microscopy; semiconductor device packaging; semiconductor device reliability; Cu; HAST; LED pn junction reverse leakage path; bandgap emission; copper leadframe migration; energy dispersive X-ray microanalysis; failure analysis; highly-accelerated temperature and humidity stress test; infra-red photoemission microscopy; moisture related failure rate; optocoupler light emitting diodes; plastic packaged optocoupler; reverse bias leakage current; scanning electron microscopy; surface copper concentration; Copper; Dispersion; Failure analysis; Leakage current; Light emitting diodes; Photoelectricity; Plastic packaging; Scanning electron microscopy; X-ray detection; X-ray detectors;
Conference_Titel :
Electronics Packaging Technology, 2003 5th Conference (EPTC 2003)
Print_ISBN :
0-7803-8205-6
DOI :
10.1109/EPTC.2003.1271543