Atomic layer deposition of ferroelectric PbTiO₃(PTO), Pb(Zr,Ti)O₃(PZT) thin films and its component oxide films were attempted using the Pb(DMAMP)₂, Ti(Oi-Pr)₄ or Ti(Ot-Bu)₄, and Zr(Ot-Bu)₂(DMAMP)₂ as the Pb-, Ti- and Zr-precursors, respectively, and H₂O as oxidant at a wafer temperature of 200℃ on Ir/IrO₂/SiO₂/Si substrate. The ALD characteristics of the component oxides, PbO, TiO₂, and ZrO₂ films were investigated in detail for determining the ALD conditions of PTO and PZT thin films. The stoichiometric PTO thin films were grown by a proper control of the cycle ratio of the PbO and TiO₂ cycles. The increase of the PTO film growth rate due to the cayalytic effect was observed compared to its component oxide films for both processes using Ti(Oi-Pr)₄ or Ti(Ot-Bu)₄. Two different post-deposition annealing method, i.e. slow and fast furnace annealing at 600℃, were used to crystallize the as-grown amorphous PTO films. The ferroelectric switching behaviors of the crystallized films were confirmed. The surface morphologies, local ferroelectric properties and leakage current behaviors of PbTiO₃ thin films, which were annealed using fast and slow furnace annealing methods, were investigated by scanning electron microscopy (SEM), piezo-force microscopy (PFM) and conductive atomic-force microscopy (CAFM). The higher growth rate of PTO film grown using Ti(Oi-Pr)₄ due to the higher growth rate of TiO₂ film compared to the case using Ti(Ot-Bu)₄ resulted in less dense PTO film with the higher density of micro-pores inside as well as surface of film after the fast furnace annealing. Slow furnace annealing improved the surface morphology of PTO film and reduced the micro-pore density. In case of PTO film grown using Ti(Oi-Pr)₄, slow-furnace annealed film showed lower local-leakage current compared to fast-furnace annealed film, whereas PTO films grown using Ti(Ot-Bu)₄ showed the opposite results. The local ferroelectric polarization switching was observed under the DC bias of 5V.

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