Fabrication and testing of through-silicon vias used in three-dimensional integration

Autor: A. Kamto, Leonard W. Schaper, Susan L. Burkett, I. U. Abhulimen, Y. Liu
Rok vydání: 2008
Předmět:
Zdroj: Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures. 26:1834-1840
ISSN: 1520-8567
1071-1023
DOI: 10.1116/1.2993174
Popis: The formation of through-silicon vias (TSVs) provides a vertical interconnect scheme that can be used in three-dimensional stacking technologies. A sloped via sidewall is essential for conformal coverage of via lining materials deposited in subsequent steps that provide insulation (SiO2), barrier (TaN), and metal seed (Cu) layers. In this article, via sidewall angles in the range of 83°–90° are investigated resulting in variable degrees of conformal lining of the insulation, barrier, and seed layers. Via insulation is deposited by plasma enhanced chemical vapor deposition, while barrier and seed layers are deposited by sputtering. A modified Bosch process, using a deep reactive ion etch tool, allows formation of differing via profiles in silicon substrates. Cross-sectional views of via profiles showing the coverage of lining materials (SiO2, TaN, and Cu) are examined with a scanning electron microscope. For a constant via sidewall angle, variable aspect ratios allow us to determine the specific via profil...
Databáze: OpenAIRE