| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device having a ferroelectric capacitor having much better polarization characteristics than before, and to provide a manufacturing method of the semiconductor device. SOLUTION: The ferroelectric capacitor 30 comprising a lower electrode 26, a ferroelectric film 27, and an upper electrode 28 is formed on a silicon substrate 10 in which transistors T1, T2, and the like are formed. The lower electrode 26 is formed by a conductor having (001) orientation with a thermal coefficient of expansion that is larger than that of a ferroelectric substance. The aspect ratio (thickness/width) of the lower electrode 26 is set to, for example, not less than 1/2. After the ferroelectric capacitor 30 is formed, it is heat-treated at temperature not less than the Curie point of the ferroelectric substance, and then is cooled to room temperature. In the cooling process, compressive stress in an in-plane direction is applied to the ferroelectric substance due to the difference in the thermal coefficent of expansion, and a (c) axis in the ferroelectric substance is oriented in a thickness direction (vertical direction to a substrate surface). COPYRIGHT: (C)2008,JPO&INPIT
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