| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for producing a lithium tantalate (LT) substrate, by which the defects caused by pyroelectricity can be uniformly improved and excellent reproductivity and production efficiency can be attained. <P>SOLUTION: The method for producing the LT substrate comprises heat treating an LT substrate, reduced by one metal element selected from the group comprising Ca, Al, Ti and Si, at a temperature not higher than the Curie temperature under a reduced pressure atmosphere of a vacuum degree of >20 to≤40 Pa. By this method, the reduced LT substrate is heat treated in the environment, wherein the diffusion of oxygen vacancies occurs, but the number of the oxygen vacancies does not increase. Thereby, the concentration of the oxygen vacancies within the LT substrate surface can be made uniform. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
