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Structure of vapor-phase deposited Al-Ge thin films and Al-Ge intermediate layer bonding of Al-based microchannel structures

Published online by Cambridge University Press:  31 January 2011

W.J. Meng*
Affiliation:
Department of Mechanical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803
D.J. Miller
Affiliation:
Electron Microscopy Center and Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

Al-based high-aspect-ratio microscale structures (HARMS) are basic building blocks for all-Al microdevices. Bonding of Al-based HARMS is essential for device assembly. In this paper, bonding of Al-based HARMS to flat Al plates using Al-Ge thin film intermediate layers is investigated. The structure of sputter codeposited Al-Ge thin films was studied by high-resolution transmission electron microscopy as a function of the average film composition. The structure of the interface region between Al-based HARMS bonded to flat Al plates is studied by combining focused ion beam sectioning and scanning electron microscopy. An extended bonding interface region, ∼100 μm in width, is observed and suggested to result from liquidus/solidus reactions as well as diffusion of Ge in solid Al at the bonding temperature of 500 °C. The extended interface region is suggested to be beneficial to Al-Al bonding via Al-Ge intermediate layers.

Type
Articles
Copyright
Copyright © Materials Research Society 2009

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