Wafer-Bonding Technologies and Strategies for 3D ICs

  • Shari FarrensEmail author
Part of the Integrated Circuits and Systems book series (ICIR)


Wafer bonding has often been described as a key enabling step for three-dimensional (3D) integration. This is the processing step in which the individual wafers are aligned and bonded so that the benefits of the layer-to-layer interconnects can be realized. Many of the alignment techniques and bonding methods have evolved from microelectromechanical system (MEMS) fabrication methods. The fundamental difference between MEMS and 3D integration is that the alignment accuracy had to be improved by 5–10 times. This has led to an evolution in the equipment platforms which are now able to achieve micron and submicron alignment accuracies in the final products. The following sections of this chapter will describe the process flow (align, fixture, and bond) and describe the options available, with enough details to determine the appropriate methods for a specific device application.

Wafer-Bonding Equipment Overview

Wafer-bonding equipment is available in manual and automated...


Alignment Accuracy Wafer Bonding Bottom Wafer Overlay Accuracy Formic Acid Vapor 
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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.SUSS MicroTecWaterbury CenterUSA

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