Submicron Cu/Sn Bonding Technology With Transient Ni Diffusion Buffer Layer for 3DIC Application

Author

Yao-Jen Chang ; Yu-Sheng Hsieh ; Kuan-Neng Chen

Author_Institution

Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan

Volume

35

Issue

11

fYear

2014

fDate

Nov. 2014

Firstpage

1118

Lastpage

1120

Abstract

A submicron Cu/Sn bonding with transient Ni buffer layer at 225 °C is demonstrated to overcome current 5-μm Cu/Sn physical limitation. The 10-nm Ni layer suppresses immense Cu/Sn interdiffusion during heating step prior to major bonding process. When the temperature is close to the Sn melting point, the Ni layer dissolves and molten Sn gives successful submicrometer Cu/Sn bonding. The excellent mechanical strength and electrical performance of this scheme show the great potential for future and highly dense 3D interconnects.

Keywords

buffer layers; chemical interdiffusion; copper alloys; integrated circuit bonding; mechanical strength; melting point; nickel; three-dimensional integrated circuits; tin alloys; 3D interconnects; 3DIC; Cu-Sn; Ni; electrical performance; heating step; interdiffusion; mechanical strength; melting point; size 10 nm; size 5 mum; submicron bonding technology; temperature 225 degC; transient diffusion buffer layer; Bonding; Buffer layers; Nickel; Reliability; Three-dimensional displays; Tin; Transient analysis; 3D integration; Cu/Sn bonding; transient Ni buffer layer;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2014.2358212

Filename

6912994