Copper alloy sputtering target, process for producing the same and semiconductor element wiring
View Patent ↗A copper alloy sputtering target is provided and contains 0.01 to (less than) 0.5 wt % of at least one element selected from Al or Sn, and containing Mn or Si in a total amount of 0.25 wtppm or less. The above copper alloy sputtering target allows the formation of a wiring material for a semiconductor element, in particular, a seed layer being stable, uniform and free from the occurrence of coagulation during electrolytic copper plating and exhibits excellent sputtering film formation characteristics. A semiconductor element wiring formed with this target is also provided.
1. A copper alloy sputtering target for forming a thin film seed layer for semiconductor wiring, the sputtering target consisting of 0.01 to less than 0.5 wt % of Al, Si or both of Si and Mn in a total amount of 0.03 wtppm to 0.25 wtppm, at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As in a total amount of 1.0 wtppm or less, and the remainder being Cu and inevitable impurities, said inevitable impurities having a total content of 1 wtppm or less and consisting of elements excluding Cu, Al, Mn, Si, said at least one additive element, and gas component elements, and said copper alloy sputtering target having an average crystal grain size of 100μm or less and a variation of the average crystal grain size of within ±20%.
2. The copper alloy sputtering target according to claim 1 , wherein said copper alloy sputtering target has 0.05 to 0.2 wt % of Al.
3. The copper alloy sputtering target according to claim 2 , wherein said total amount of said at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As is 0.3 wtppm or less.
4. The copper alloy sputtering target according to claim 1 , wherein said total amount of said at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As is 0.13 wtppm to 1.0 wtppm.
5. The copper alloy sputtering target according to claim 4 , wherein said total amount of said at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As does not exceed 0.5 wtppm.
6. The copper alloy sputtering target according to claim 5 , wherein said total amount of said at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As does not exceed 0.3 wtppm.
7. The copper alloy sputtering target according to claim 1 , wherein the content of Si in the sputtering target is 0.03 to 0.19 wtppm and the content of Mn in the sputtering target is 0.002 to 0.22 wtppm.
8. The copper alloy sputtering target according to claim 1 , wherein said copper alloy sputtering target has 0.05 wtppm or less of Na and K, respectively and 1 wtppb or less of U and Th, respectively as inevitable impurities.
9. The copper alloy sputtering target according to claim 1 , wherein said copper alloy sputtering target has 0.02 wtppm or less of Na and K, respectively and 0.5 wtppb or less of U and Th, respectively as inevitable impurities.
10. A copper alloy sputtering target for forming a thin film seed layer for semiconductor wiring, the sputtering target consisting of 0.01to less than 0.5 wt % of Al, Si or both of Si and Mn in a total amount of 0.03 wtppm to 0.25 wtppm, at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As in a total amount of 1.0 wtppm or less, and the remainder being Cu and inevitable impurities said inevitable impurities, excluding gas component elements, having a total content of 1 wtppm or less and consisting of elements other than Cu, Al, Mn, Si, said at least one additive element and gas component elements, said gas component elements including 5 wtppm or less of oxygen, 2 wtppm or less of nitrogen, and 2 wtppm or less of carbon, and said copper alloy sputtering target having an average crystal grain size of 100 μm or less and a variation of the average crystal grain size of within ±20%.
11. The copper alloy sputtering target according to claim 10 , wherein said copper alloy sputtering target has 0.05 to 0.2 wt % of Al.
12. The copper alloy sputtering target according to claim 10 , wherein said total amount of said at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As is 0.3 wtppm or less.
13. The copper alloy sputtering target according to claim 10 , wherein the content of Si in the sputtering target is 0.03 to 0.19 wtppm and the content of Mn in the sputtering target is 0.002 to 0.22 wtppm.
14. The copper alloy sputtering target according to claim 10 , wherein said total amount of said at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As is 0.13 wtppm to 1.0 wtppm.
15. The copper alloy sputtering target according to claim 10 , wherein said copper alloy sputtering target has 0.05 wtppm or less of each of Na and K and 1 wtppb or less of each of U and Th as inevitable impurities.
16. The copper alloy sputtering target according to claim 10 , wherein said copper alloy sputtering target has 0.02 wtppm or less of each of Na and K and 0.5 wtppb or less of each of U and Th as inevitable impurities.
17. The copper alloy sputtering target according to claim 10 , wherein said average crystal grain size is 61 to 96 μm.
18. The copper alloy sputtering target according to claim 1 , wherein said average crystal grain size is 61 to 96 μm.
19. A copper alloy sputtering target for forming a thin film seed layer for semiconductor wiring, the sputtering target consisting of 0.01 to less than 0.5 wt % of Al, both Mn and Si in a total amount of 0.03 wtppm to 0.25 wtppm, at least one additive element selected from the group consisting of Sb, Zr, Ti, Cr, Ag, Au, Cd, In and As in a total amount of 1.0 wtppm or less, and the remainder being Cu, and said copper alloy sputtering target having an average crystal grain size of 100 μm or less and a variation of the average crystal grain size of within ±20%.
20. The copper alloy sputtering target according to claim 19 , wherein the content of Si in the sputtering target is 0.03 to 0.19 wtppm and the content of Mn in the sputtering target is 0.002 to 0.22 wtppm.