| 摘要 |
<p>PURPOSE:To remarkably shorten the time necessary for annealing and to eliminate the need for a furnace utilized for annealing by constituting the title annealing method so that lithium tantalate single crystal is grown and successively annealing of single crystal is performed in the same furnace. CONSTITUTION:Lithium tantalate single crystal 15 which has been grown by immersing seed crystal 11 in melt 7 for growing lithium tantalate single crystal in a furnace core pipe 3 provided with a heater 2 for heating to the outside is separated from the melt 7 by lowering a crucible 4 held with the melt 7 therein. Then it is slowly cooled to the annealing temp. of single crystal 15 by controlling the heater 2 and furthermore after holding it at this annealing temp. only for a prescribed time, it is slowly cooled and taken out from the furnace core pipe 3.</p> |
