Determination of Thermal Fatigue Delamination of Die Attach Materials for High-Brightness LEDs

Author

Zhang, Guangchen ; Feng, Shiwei ; Zhu, Hui ; Liu, Jing ; Li, Jingwan ; Guo, Chunsheng

Author_Institution

Sch. of Electr. Inf. & Control Eng., Beijing Univ. of Technol., Beijing, China

Volume

24

Issue

5

fYear

2012

fDate

3/1/2012 12:00:00 AM

Firstpage

398

Lastpage

400

Abstract

The thermal fatigue delamination interface of die attach materials in high-brightness light-emitting diodes (HB LEDs) is determined using a noninvasive approach. Failure analysis of HB LEDs containing Au80Sn20 eutectic alloy and silver paste as die attach materials is performed by monitoring the changes in the partial thermal resistances in differential structure function curves of the HB LEDs through power cycling experiments. The results suggest that delamination of the Au80Sn20 eutectic and silver paste materials occurs at the chip-to-die attach interface and die attach-to-heat sink interface, respectively, which is consistent with cross-sectional scanning electron microscope analysis.

Keywords

delamination; eutectic alloys; failure analysis; gold alloys; heat sinks; light emitting diodes; microassembling; silver alloys; thermal resistance; thermal stress cracking; tin alloys; Ag; Au-Sn; chip-to-die attach interface; cross sectional scanning electron microscope analysis; die attach material; die attach-to-heat sink interface; differential structure function; eutectic alloy; failure analysis; high brightness LED; partial thermal resistance; power cycling; silver paste; thermal fatigue delamination; Delamination; Fatigue; Light emitting diodes; Materials; Microassembly; Reliability; Silver; Light-emitting diodes (LEDs); structure function; thermal interface material;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2011.2179925

Filename

6105525