Adhesion Investigation Between Metal and Benzocyclobutene (BCB) Polymer Dielectric Materials in 3-D Integration Applications

Author

Jian-Yu Shih ; Wen-Chun Huang ; Cheng-Ta Ko ; Zheng Yang ; Sheng-Hsiang Hu ; Jihperng Leu ; Chou, Keng C. ; Kuan-Neng Chen

Author_Institution

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

Volume

14

Issue

3

fYear

2014

fDate

Sept. 2014

Firstpage

914

Lastpage

920

Abstract

In this paper, the interfacial adhesion strength between metal layer and benzocyclobutene (BCB) polymer dielectric in 3-D integration applications is investigated. The effects of layer thickness, layer stacking order, and additional adhesion layer of titanium (Ti) layer between copper (Cu) and BCB polymer are investigated. Surprisingly, the conventional titanium adhesion layer commonly used in the semiconductor industry weakens the interfacial adhesion strength between copper and BCB. Additionally, to figure out the interfacial adhesion mechanisms, the interfacial structures probed by sum-frequency-generation vibrational spectroscopy are correlated to the adhesion strengths measured from corresponding sample interfaces. It is found that ordered C-H groups at the metal/BCB interface, such as titanium/BCB or molybdenum/BCB, lead to weak interfacial adhesion strength, whereas disordered interfaces, i.e., copper/BCB, lead to strong interfacial adhesion strength.

Keywords

adhesion; conducting polymers; copper; dielectric materials; integrated circuit interconnections; interface structure; optical frequency conversion; three-dimensional integrated circuits; titanium; 3D integration applications; Cu; Ti; adhesion layer; benzocyclobutene polymer dielectric materials; copper-BCB interface; disordered interfaces; interfacial adhesion strength; interfacial structures; layer stacking order; layer thickness; metal layer; metal-BCB interface; sum-frequency-generation vibrational spectroscopy; titanium layer; Adhesives; Copper; Polymers; Spectroscopy; Titanium; 3-D integration; Adhesion; benzocyclobutene (BCB);

fLanguage

English

Journal_Title

Device and Materials Reliability, IEEE Transactions on

Publisher

ieee

ISSN

1530-4388

Type

jour

DOI

10.1109/TDMR.2014.2343793

Filename

6866908