| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a low-oxygen titanium material used for a target for semiconductor use by a Kroll method. SOLUTION: In the method for manufacturing the low-oxygen titanium material, sponge titanium after vacuum separation is cooled in a reactor vessel and a nitride film is formed on the surface of the sponge titanium in the reactor vessel and then the sponge titanium is taken out of the reactor vessel and cut or crushed. The nitride film forms desirably by changing low-oxygen nitrogen gas having a ratio of the partial pressure of nitrogen to the partial pressure of oxygen of >=20 into the reactor vessel and to change the nitrogen gas after the temperature in the central part of the sponge titanium reaches <=200 deg.C in the reactor vessel.
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