J. Phys. IV France
Volume 08, Numéro PR9, December 1998
2nd European Meeting on Integrated Ferroelectrics
Page(s) Pr9-239 - Pr9-242
2nd European Meeting on Integrated Ferroelectrics

J. Phys. IV France 08 (1998) Pr9-239-Pr9-242

DOI: 10.1051/jp4:1998946

Direct wafer bonding : A new fabrication method for ferroelectric-silicon heterostructures

M. Alexe, R. Scholz, G. Kästner, A. Pignolet and U. Gösele

Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle/Saale, Germany

Ferroelectric-semiconductor heterostructures were fabricated using direct wafer bonding. Polycrystalline Bi4Ti3O12 ferroelectric thin films were deposited on 3" silicon wafers by chemical solution deposition. The films were polished and then directly bonded to silicon wafers in a micro-cleanroom. After thermal annealing in air at 500°C for 12 hours, the bonding energy increases up to 1.5 J/m2. High resolution transmission electron microscopy shows a significant difference between the bonded and reacted interfaces. A Metal-Ferroelectric-Silicon (MFS) structure containing the ferroelectric-Si bonded interface was achieved by polishing down and etching the handling wafer. Capacitance-voltage (C-V) and current-voltage (I-V) characteristics were measured for the Bi4Ti3O12/Si heterostructures with a bonded interface.

© EDP Sciences 1998