No.

Raw materials

Heat treatment conditions

Yttrium

Silicon

Temp.

Duration

Atmosphere

(purity)

[O]

(˚C)

hr

1

powder (99.9%)

8.3 mm (1.17%)

1100

5

Quartz tube

2

powder (99.9%)

8.3 mm (1.17%)

1090

5

Vacuum

3

powder (99.9%)

8.3 mm (1.17%)

1500

1

Vacuum

4

ingot (99.9%)

−100 Me’ (0.081%)

1600

0.5

0.1 MPa Ar

5

ingot (99.9%)

−100 Me’ (0.081%)

1600

1100

0.5

12

0.1 MPa Ar