| 摘要 |
PURPOSE:To reduce the decrease of capacitance after reading/writing of 10<15> time without the generation of a space charge due to polarization and inversion by forming a ferroelectric film on an electrode on a semiconductor substrate and applying an electric field between a surface and an electrode and polarizing the ferroelectric film at a temperature below a transition temperature. CONSTITUTION:A silicon dioxide film 102 is formed as a layer insulating film on a silicon substrate 101, and then Pt 104 of a lower electrode is formed through Ti 103 of a contact layer, and polycrystalline PZT 105 polycrystalline/ showing a ferroelectric characteristic is laminated thereon, and after that, heat treatment is applied to the PZT film 105 with a corona discharge in air, and an external voltage 106 is controlled so that a voltage applied to the PZT film becomes 5 volts. Consequently, a dipole moment in each divided region is oriented in the direction of a bias voltage, and the PZT film 105 is polarized. After that, the succeeding processes are carried out in the temperature below the transition temperature of the PZT film. |
