| 摘要 |
PURPOSE:To increase the relative permittivity of ferroelectric layer for increasing the accumulated charge amount by a method wherein a MgO layer as an insulator is formed on the lower side of lower electrode of a capacitor comprising an upper electrode, ferroelectric layer and lower electrode. CONSTITUTION:Impurities are selectively implanted in the surface of a Si substrate 11 to form a diffused layer 12 and then a SiO2 layer 13 is formed on the whole surface. Next, single crystalline Si is epitaxially grown by ELO and then after the formation of a single crystal Si layer 14, a MgO layer 15 is epitaxially grown on the layer 14. Next, the periphery of the MgO layer 15 is removed leaving the epitaxially grown layer of the MgO layer 15 only intact. Later, Ti or Ta layer 16 is formed by CVD step etc. Next, a Pt layer 17 as a lower electrode is formed on the Ti or Ta layer 16, the MgO layer 15 and the SiO2 layer 13. In such a constitution, the MgO layer 15 is provided on the lower side of the Ti layer 17 as the lower electrode but on the upper side of the single crystal Si layer 14 so that the relative permittivity of a ferroelectric layer 18 may be increased thereby enabling the accumulated charge amount to be increased. |
