| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing lithium tantalate single crystals which can produce single crystals excellent in homogeneity of lithium tantalate used as an optical element.SOLUTION: A method for producing lithium tantalate single crystals includes: a molten liquid preparation step of preparing a molten liquid 4 by melting raw materials comprising a lithium-containing compound and a tantalum-containing compound; and a single crystal growth step of growing lithium tantalate single crystals 6 by preparing a seed crystal 5, immersing a tip of the seed crystal 5 into the molten liquid 4, and then pulling up the seed crystal 5. In the molten liquid preparation step, the raw materials are melted in a fluoride-containing gas atmosphere. The concentration of fluorides (CF, CHF, CHF, HF, Fand the like) in the fluoride-containing gas is maintained in a range of 0.01-100 vol.%. |
