| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a forming method for a PZT thin film which facilitates the formation of the PZT thin film having the uniform direction of spontaneous polarization along the thickness direction and having a high orientation property and favorable crystallinity, a BAW resonator having, as a piezoelectric thin film, the PZT thin film which has the uniform direction of spontaneous polarization along the thickness direction and has the high orientation property and favorable crystallinity, and a filter for UWB using the same. <P>SOLUTION: A PZT thin film 30b is formed by coating one surface side of a substrate for growth comprising a base substrate 10 and a first conductive layer 20a with a solution obtained by dissolving a metal alkoxide containing a component element of PZT in a solvent, removing the solvent to form a precursor film 30a of a PZT thin film 30b, and then annealing and crystallizing the precursor film 30a by a laser annealing method while applying an electric field along the thickness direction of the precursor film 30. Then, the piezoelectric film 30 constituted of a portion of the PZT thin film 30b is formed, a lower electrode 20 constituted of a portion of the first conductive layer 20a is formed, and an upper electrode 40 is formed. <P>COPYRIGHT: (C)2008,JPO&INPIT |
