Manganese alloy sputtering target and method for producing the same
View Patent ↗A manganese alloy sputtering target characterized in that oxygen is 1000 ppm or less, sulfur is 200 ppm or less and a forged texture is provided, and a method for producing a forged manganese alloy target stably by eliminating the drawbacks of manganese alloy that it is susceptible to cracking and has a low rupture strength. A manganese alloy sputtering target which can form a thin film exhibiting high characteristics and high corrosion resistance while suppressing generation of nodules or particles is thereby obtained.
1. A method of manufacturing a manganese alloy sputtering target comprising the steps of:
obtaining a manganese alloy ingot by a melting method selected from the group consisting of an inductive melting method, an arc melting method, and an electron beam melting method, and
forging said manganese alloy ingot at an average actual strain rate of 1×10 −2 to 2×10 −5 (1/s) to form a forged manganese alloy sputtering target consisting of at least one of Ni, Pd, Pt, Rh, Ir, Au, Ru, Os, Cr and Re, and remnant Mn 39.8 to 98 at %,
said forging step being performed at 0.75 Tm(K)≦T(K)≦0.98 Tm(K), wherein T(K) is the forging temperature and Tm(K) is the melting point of said manganese alloy.
2. A method according to claim 1 , wherein forging is performed at 0.80 Tm(K)≦T(K)≦0.90 Tm(K).
3. A method according to claim 2 , wherein forging is performed at 30%≦draft≦99%.
4. A method according to claim 3 , wherein said forging is performed as upset forging or die forging.
5. A method according to claim 4 , wherein forging is performed in a vacuum or under an inert gas atmosphere.
6. A method according to claim 5 , wherein said forging step includes forming the manganese alloy sputtering target such that the target contains 1000 ppm or less of oxygen and 200 ppm or less of sulfur.
7. A method according to claim 6 , wherein said forging step includes forming the manganese alloy sputtering target with one or less oxide particles per unit area (100 μm×100 μm) that has a particle diameter of 5 μm or greater.
8. A method according to claim 7 , wherein said forging step includes forming the manganese alloy sputtering target with a single phase equiaxed grain structure.
9. A method according to claim 8 , wherein said forging step includes forming the manganese alloy sputtering target with a crystal grain diameter of 500 μm or less.
10. A method according to claim 1 wherein forging is performed at 30%≦draft≦99%.
11. A method according to claim 1 , wherein said forging is performed as upset forging or die forging.
12. A method according to claim 1 , wherein forging is performed in a vacuum or under an inert gas atmosphere.
13. A method according to claim 1 , wherein said forging step includes forming the manganese alloy sputtering target such that the target contains 1000 ppm or less of oxygen and 200 ppm or less of sulfur.
14. A method according to claim 1 , wherein said forging step includes forming the manganese alloy sputtering target with one or less oxide particles per unit area (100 μm×100 μm) that has a particle diameter of 5 μm or greater.
15. A method according to claim 1 , wherein said forging step includes forming the manganese alloy sputtering target with a single phase equiaxed grain structure.
16. A method according to claim 1 , wherein said forging step includes forming the manganese alloy sputtering target with a crystal grain diameter of 500 μm or less.