Evaluation of ultrasonic vibration energy for copper-to-copper bonding by flip-chip bonding technology

Author

Arai, Yutaro ; Miyamoto, Yutaka ; Nimura, Masatsugu ; Tomokage, Hajime

Author_Institution

R&D Div., Toray Eng. Co., Ltd., Otsu, Japan

fYear

2014

fDate

23-25 April 2014

Firstpage

658

Lastpage

661

Abstract

The ultrasonic vibration energy for Cu-Cu bonding by flip-chip bonding technology was evaluated in ambient air. Transmissibility of ultrasonic vibration is assumed to be different in bump structure with height or low stiffness. Therefore, we investigated the bonding strength of Cu bump with the different aspect ratio (bump height: 5 μm, 20 μm, and 40 μm). As a result, the Cu bumps with 20 μm height were properly bonded with sufficient bonding strength, compared with the others. In addition, there were no significant voids at Cu-Cu interface of well-bonded Cu bump.

Keywords

copper; flip-chip devices; ultrasonic bonding; vibrations; Cu-Cu; Cu-Cu interface; aspect ratio; bonding strength; bump structure; copper-to-copper bonding; flip-chip bonding technology; size 20 mum; size 40 mum; size 5 mum; ultrasonic vibration energy; Acoustics; Bonding; Flip-chip devices; Plasma temperature; Scanning electron microscopy; Substrates; Vibrations; Cu bump; Cu-Cu bonding; Flip-chip bonding; Low temperature bonding; Ultrasonic vibration;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronics Packaging (ICEP), 2014 International Conference on

Conference_Location

Toyama

Print_ISBN

978-4-904090-10-7

Type

conf

DOI

10.1109/ICEP.2014.6826762

Filename

6826762