| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method which allows the production of a highly insulating and highly stable LTGA (La<SB>3</SB>Ta<SB>0.5</SB>Ga<SB>5.5-x</SB>Al<SB>x</SB>O<SB>14</SB>) single crystal usable for a piezoelectric element of a highly reliable combustion pressure sensor useful for measuring the combustion pressure in a combustion chamber of an internal combustion engine. <P>SOLUTION: In the method for producing the LTGA single crystal from a polycrystalline starting raw material prepared by using a mixture of La<SB>2</SB>O<SB>3</SB>, Ta<SB>2</SB>O<SB>5</SB>, Ga<SB>2</SB>O<SB>3</SB>, and Al<SB>2</SB>O<SB>3</SB>, a mixture having a composition represented by formula: y(La<SB>2</SB>O<SB>3</SB>)+(1-x-y-z)(Ta<SB>2</SB>O<SB>5</SB>)+z(Ga<SB>2</SB>O<SB>3</SB>)+x(Al<SB>2</SB>O<SB>3</SB>), wherein 0<x≤0.40/9, 3.00/9<y≤3.23/9, and 5.00/9≤z<5.50/9, is used as the polycrystalline starting raw material, and the LTGA single crystal is grown by using the crystal growth axis as the z-axis. It is preferable to subject the grown LTGA single crystal to a vacuum heat treatment. <P>COPYRIGHT: (C)2011,JPO&INPIT |
