First in Operando SEM Observation of Electromigration-Induced Voids in TSV Structures

Simon Gousseau (1, 2) , Stéphane Moreau (2) , David Bouchu (2) , Alexis Farcy (3) , Pierre Montmitonnet (1) , Karim Inal (1) , François Bay (1)

1 CEMEF - Centre de Mise en Forme des Matériaux
2 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
3 ST-CROLLES - STMicroelectronics [Crolles]

Since the early beginning of the integrated circuits, electromigration is a reliability issue of first interest. In 3-dimensionnal structures, electromigration is responsible for the formation of voids in lines connected to the Through Silicon Via (TSV). To our knowledge, this paper presents the first in operando electromigration experiment in a Scanning Electron Microscope (SEM) performed for 3D integration. The experimental protocol, including sample preparation and temperature regulation, is detailed. A current of 25 mA is injected in a structure heated at 350 °C for about 900 h. The evolution of voids is monitored and explained. Void growth occurs step by step, so that the microstructure may be assumed to play a major role in the depletion mechanism. The behavior of the electrical resistance is analyzed using the SEM micrographs

Domaines: Sciences de l'ingénieur [physics]; Matériaux

Simon Gousseau, Stéphane Moreau, David Bouchu, Alexis Farcy, Pierre Montmitonnet, et al.. First in Operando SEM Observation of Electromigration-Induced Voids in TSV Structures. 39th International Symposium for Testing and Failure Analysis - ISTFA 2013, Nov 2013, San Jose, California, United States. pp.59-68 - ISBN 978-1-62708-022-4. ⟨hal-01052908⟩