Here is the abstract you requested from the DPC_2007_3D technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Self Assembly of Die to Wafer using Direct Bonding Methods and Capillarity Techniques|
|Keywords: 3D integration, self assembly, direct bonding|
|Nowadays 3D integration technology is investigated in every microelectronic device fabrication stages. Semiconductor layers, transistors, wafers and chips are piled up to create new functionalities, enhance device performances or develop innovative systems on a chip. 3D integration technology enables to bring them together in one chip. This can be done either as a sequence of bonding and processing stages or by the bonding of dies processed in parallel. However the decrease in die sizes and the higher complexity of heterogeneous device designs creates a demand of new hybridization techniques. Direct bonding and self-assembly are promising techniques to overcome “pick-and-place” tool issues on precise alignment and manipulations of microparts. In literature, self-assembly is achieved by shape recognition surface and/or surface functionalization with self assembled monolayers (SAM) . We have developed an original self-assembly method, using surface preparation methods which are inherited from wafer bonding to create hydrophobic and hydrophilic binding sites. The alignment is obtained on the hydrophilic zones by capillarity forces. The bonding strength is high enough so that the assembly can handle post processing, such as thinning down or trough via etching for interconnects. We will present this technique and review our latest results on die to wafer bonding via direct bonding techniques and alignment with self assembly. As an example of application the achievement of optical link upon CMOS will be presented. We will also discuss on the impact of key parameters such as surface functionalization techniques and water drop volumes. Reference: : X. Xiong, Y. Hanein, J. Fang, Y. Wang, W. Wang, D.T. Schwarz, K.F. Böhringer, Controlled Multibatch Self-Assembly of Microdevices, Journal of Micro Electromechanical Systems, Volume 12, no. 2, April 2003.|
|François Grossi, Ph.D. Student
38 054 Grenoble CEDEX 9,