Watchmen: Tales of the Black Freighter  720p .1. Technical Field
The present invention relates generally to a method for producing an object, such as an optical component or optical disk, and a piezoelectric material used for a piezoelectric element in the method. More particularly, the invention relates to a method for producing an object including a piezoelectric material, which is preferably a bismuth (Bi)-based piezoelectric material and an object produced by the method.
2. Related Art
Various optical disks, optical heads, and optical driving devices are provided with a piezoelectric material. For example, in order to focus an optical beam onto an information recording surface of an optical disk, an optical head with a cantilever actuator is provided. The actuator is driven by a piezoelectric element that is fixed onto the cantilever, and the tip of the optical head is moved to the information recording surface of the optical disk. Therefore, the information recording surface can be scanned by the optical beam.
In general, a piezoelectric material, such as a lead zirconate titanate (PZT) material or an apatite glass (APG) material, is used for the piezoelectric element. The piezoelectric element made of a PZT material or APG material has a structure in which a lower electrode, a piezoelectric material layer, and an upper electrode are sequentially laminated, and the piezoelectric material layer is polarized in a thickness direction of the laminated structure. If a driving voltage is applied between the lower electrode and the upper electrode, a distortion is generated in the piezoelectric material layer, and the cantilever actuator driven by the distortion is deformed. Thereby, the optical head can be moved.
On the other hand, in a semiconductor device or the like, a piezoelectric material, which is preferably a bismuth-based piezoelectric material, is used for a piezoelectric element. It is known that the bismuth-based piezoelectric material has better piezoelectric properties and a lower dependency on environmental conditions, such as temperature, and thus has higher reliability. Thus, there is a demand for a piezoelectric material containing a bismuth- 0b46394aab