Abstract
The wedge microstructure of AlSi1 wire bonds as well as the interface between the bonding wire and the Cu/Ni/Au metallization layer especially for chip on board (COB) assemblies was investigated by focused ion beam (FIB), transmission electron microscopy (TEM), and microhardness measurements. The as-received wires were characterized by fiber texture of 〈111〉 and 〈100〉 orientation. With increasing ultrasonic (US) power, the results indicate recrystallization of the grain structure and decreasing microhardness inside the bonded wedge contacts. The interface between the AlSi1 wire and the Cu/Ni/flash-Au metallization layer of the optimized bonds consists of a closed crystalline Au layer. Above this Au layer, a second zone consisting of intermetallic phases was analyzed and identified by electron diffraction as Au8Al3.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
B. Kämpfe and E. Auerswald, “Entwicklung von Röntgengeräten der Prozeßanalytik,” Report No. IZM/2/F/390 (Berlin: Fraunhofer IZM, 2003).
F. Farrassat (Ph.D. Dissertation, Technical University, Berlin, 1996).
K.-D. Lang, “Qualitätssicherung im Zyklus II der Herstellung Elektronischer Bauelemente am Beispiel des Drahtbondens” (Berlin: Habilitation Humboldt Universität, 1988).
U. Geißler, M. Schneider-Ramelow, and K.-D. Lang, GMM 2004 Fachbericht 44 (Berlin: VDE Verlag GmbH, 2004), pp. 399–404.
“Destructive Pull Test,” Mil STD 883D, Method 2021 and Method 2011.
Y. Liu and J.W. Kinzy, J. Electron. Mater. 33, 929 (2004).
U. Geißler, M. Schneider-Ramelow, K.-D. Lang, and H. Reichl, PLUS, Bd. 6, 4 (2004).
F. Osterwald (Ph.D. Dissertation, Technical University, Berlin, 1999).
B. Weiß, D. Oelschlägel, H. Kuzmany, and H. Pinger, Z. Metallkd. 56, 312 (1965).
H. Kuzmany and B. Weiß, Z. Metallkd. 58, 190 (1967).
P. Haasen, Physikaische Metallkunde (Berlin: Akademie-Verlag, 1985).
N. Murdeshwar and J.E. Krzanowski, Metall. Mater. Trans. A 28A, 2663 (1997).
K.C. Joshi, Welding J. 50, 840 (1971).
P. Ratchev, M. Van De Peer, H.M. Ho, and B. Verlinden, Proc. IMAPS Nordic Annual Conf. 40 (Espoo, Finland: 2003), pp. 126–133.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Geißler, U., Schneider-Ramelow, M., Lang, KD. et al. Investigation of microstructural processes during ultrasonic wedge/wedge bonding of AlSi1 wires. J. Electron. Mater. 35, 173–180 (2006). https://doi.org/10.1007/s11664-006-0201-2
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s11664-006-0201-2