The paper presents fabrication of metal-ferroelectric-silicon structures by a layer transfer process via direct wafer bonding. PZT and SBT ferroelectric thin films were deposited by chemical solution deposition on 3 Pt-coated silicon wafers and subsequently crystallised by conventional thermal annealing. The ferroelectric films were polished by standard chemical mechanical polishing in order to decrease the surface roughness under 1 nm RMS and to achieve the bonding conditions. The

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... /Si wafers were directly bonded to silicon wafers using a microcleanroom set up and subsequently annealed in air at temperatures lower than 500 • C. MFS heterostructures were electrically characterised by capacitance-voltage and current-voltage measurements. The direct wafer bonding prevents formation of low permittivity layer between Si and the ferroelectric film and improves significantly the interface trap density.