Effect of Formic Acid Vapor In Situ Treatment Process on Cu Low-Temperature Bonding

被引：34

作者：

Yang, Wenhua ^{[1
]}

Akaike, Masatake ^{[1
]}

Suga, Tadatomo ^{[1
]}

机构：

[1] Univ Tokyo, Dept Precis Engn, Tokyo 1138656, Japan

来源：

IEEE TRANSACTIONS ON COMPONENTS PACKAGING AND MANUFACTURING TECHNOLOGY | 2014年 / 4卷 / 06期

关键词：

Cu/Cu direct bonding; formic acid vapor; low temperature; SURFACE; ADSORPTION; OXIDATION;

D O I：

10.1109/TCPMT.2014.2315761

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Low-temperature Cu/Cu direct bonding technology using formic acid vapor in situ treatment was developed. Effect of formic acid vapor treatment conditions on Cu surface and bonding was studied. Cu surface oxide was reduced using formic acid vapor in situ treatment at 150 and 200 degrees C, respectively. With higher temperature and longer treatment time, surface reduction is more effective. Grain boundary etching was found on chemical mechanical polished Cu film after initial treatment by formic acid. However, Cu surface roughness is minimally influenced by long-time formic acid vapor treatment. Cu film/Cu film direct bonding was realized in N-2 atmosphere with formic acid vapor in situ treatment under temperature below 200 degrees C. For lower treatment temperature, longer treatment time is required to achieve good bonding. The bonding strength is about 9.0 MPa when Cu surface is treated at 200 degrees C for 10 min.

引用

页码：951 / 956

页数：6

共 16 条

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