Volume shrinkage induced by interfacial reactions in micro joints

Author

Li, C.C. ; Zhu, Z.X. ; Chen, M.H. ; Kao, C.R.

Author_Institution

Dept. of Mater. Sci. & Eng., Nat. Taiwan Univ., Taipei, Taiwan

fYear

2013

fDate

Feb. 27 2013-March 1 2013

Firstpage

8

Lastpage

14

Abstract

In 3D-IC, solder joints of a few microns in size are used. Theoretically, there is 11.4% shrinkage in volume when Ni reacted with Sn to form Ni₃Sn₄. Surface profilometer and SEM analysis were carried out to measure the actual volume shrinkage for micro Ni/Sn/Ni sandwich structures during an isothermal annealing at 180°C for 0-7 days. The results showed there was about 7.3% shrinkage in volume and the remaining 3.2% shrinkage was released by forming voids. The internal stress and the forming of voids caused by solid state reaction might induce potential reliability issues.

Keywords

annealing; integrated circuit packaging; internal stresses; nickel; scanning electron microscopy; shrinkage; solders; three-dimensional integrated circuits; tin; voids (solid); 3D IC; Ni-Sn-Ni; SEM analysis; interfacial reaction; internal stress; isothermal annealing; micro joints; sandwich structures; solder joints; solid state reaction; surface profilometer; temperature 180 C; time 0 day to 7 day; voids; volume shrinkage; Abstracts; Joints; Nickel; Roads; Strain; Three-dimensional displays; Tin;

fLanguage

English

Publisher

ieee

Conference_Titel

Advanced Packaging Materials (APM), 2013 IEEE International Symposium on

Conference_Location

Irvine, CA

ISSN

1550-5723

Print_ISBN

978-1-4673-6093-7

Electronic_ISBN

1550-5723

Type

conf

DOI

10.1109/ISAPM.2013.6510383

Filename

6510383