The corrosion behavior of Ag alloy wire bond on Al pad in molding compounds of various chlorine contents under biased-HAST

Ying Ta Chiu, Tzu Hsing Chiang, Ping Feng Yang, Louie Huang, Chih Pin Hung, Shoji Uegaki, Kwang-Lung Lin

Research output: Chapter in Book/Report/Conference proceedingConference contribution

9 Citations (Scopus)

Abstract

The present article investigated the performance and corrosion behavior between Ag alloy wire bond and Al pad under molding compounds of different chlorine contents. The epoxy molding compounds (EMCs) were categorized as ultra-high chlorine, high chlorine and low chlorine, respectively, with 18.3 and 4.1 ppm chlorine contents. The ball bonds were stressed under 130°C/85%RH with biased voltage of 10V. The interfacial evolution between Ag alloy wire bond and Al pad was investigated in EMC of three chlorine contents after the biased-HAST test. The Ag bonding wires used in the plastic ball grid array (PBGA) package include low Ag wire (89wt%) and high Ag alloy wire (97wt%). The as bonded wire bond exhibits an average Ag-Al IMC thickness of ∼0.56 μm in both types of Ag alloy wire. Two Cu-Al IMC layers, AgAl2 and Ag4Al, analyzed by EDX were formed after 96h of biased-HAST test. The joint failed in 96h and 480h, respectively, under high chlorine content EMC. The joint lasts longer than 1056h with low chlorine content EMC. The corrosion of IMC formed between Ag alloy wire and Al pad, occurs in the high Ag content alloy wire. The results of EDX analysis indicate that the chlorine ion diffuses from molding compound to IMC through the crack formed between IMC and Al pad. Al2O3 was formed within the IMC layer. It is believed the existence of Al2O3 accelerates the penetration of the chlorine ion and thus the corrosion.

Original languageEnglish
Title of host publication2016 International Conference on Electronics Packaging, ICEP 2016
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages497-501
Number of pages5
ISBN (Electronic)9784904090176
DOIs
Publication statusPublished - 2016 Jun 7
Event2016 International Conference on Electronics Packaging, ICEP 2016 - Hokkaido, Japan
Duration: 2016 Apr 202016 Apr 22

Publication series

Name2016 International Conference on Electronics Packaging, ICEP 2016

Other

Other2016 International Conference on Electronics Packaging, ICEP 2016
CountryJapan
CityHokkaido
Period16-04-2016-04-22

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering
  • Mechanics of Materials

Fingerprint Dive into the research topics of 'The corrosion behavior of Ag alloy wire bond on Al pad in molding compounds of various chlorine contents under biased-HAST'. Together they form a unique fingerprint.

Cite this