Electrolytic copper plating method, phosphorous copper anode for electrolytic plating method, and semiconductor wafer having low particle adhesion plated with said method and anode
View Patent ↗An electrolytic copper plating method characterized in employing phosphorous copper as the anode upon performing electrolytic copper plating, and performing electrolytic copper plating upon making the crystal grain size of the phosphorous copper anode 10 to 1500 μm when the anode current density during electrolysis is 3 A/dm 2 or more, and making the grain size of the phosphorous copper anode 5 to 1500 μm when the anode current density during electrolysis is less than 3 A/dm 2 . The electrolytic copper plating method and phosphorous copper anode used in such electrolytic copper plating method is capable of suppressing the generation of particles such as sludge produced on the anode side within the plating bath, and is capable of preventing the adhesion of particles to a semiconductor wafer. A semiconductor wafer plated with the foregoing method and anode having low particle adhesion are provided.
1. An electrolytic copper plating method, comprising the steps:
employing phosphorous copper as an anode,
performing electrolytic copper plating with said anode,
making the crystal grain size of said phosphorous copper anode 100 to 1500 μm
before said step of performing electrolytic copper plating, and
forming a minute crystal layer having a crystal grain size of 1 to 100 μm on a surface of said phosphorous copper anode in advance of said step of performing electrolytic copper plating.
2. An electrolytic copper plating method according to claim 1 , wherein said crystal grain size of said phosphorous copper anode is 100 to 700 μm.
3. An electrolytic copper plating method according to claim 2 , wherein said phosphorous copper anode has a phosphorous content of 50 to 2,000 wt ppm.
4. An electrolytic copper plating method according to claim 3 , wherein a black film which has a thickness of 1000 μm or less and which has one of copper phosphide and copper chloride as a principle component is formed on said phosphorus copper anode.
5. An electrolytic copper plating method according to claim 4 , wherein said step of performing electrolytic copper plating is performed on a semiconductor wafer.
6. An electrolytic copper plating method according to claim 1 , wherein said phosphorous copper anode has a phosphorous content of 50 to 2,000 wt ppm.
7. An electrolytic copper plating method according to claim 1 , wherein a black film which has a thickness of 1000 μm or less and which has one of copper phosphide and copper chloride as a principle component is formed on said phosphorous copper anode.
8. An electrolytic copper plating method according to claim 1 , wherein said step of performing electrolytic copper plating is performed on a semiconductor wafer.
9. A phosphorous copper anode for electrolytic copper plating characterized in that phosphorous copper is used as the anode for performing electrolytic copper plating, the crystal grain size of said phosphorous copper anode is 5 to 1500 μm and said phosphorous copper anode has a surface with a minute crystal layer having a crystal grain size of 1 to 100 μm.
10. A phosphorous copper anode according to claim 9 , wherein said crystal grain size of said phosphorous copper anode is 100 to 700 μm.
11. A phosphorous copper anode according to claim 10 , wherein said phosphorous copper anode has a phosphorous content of 50 to 2,000 wt ppm.
12. A phosphorous copper anode according to claim 11 , wherein said phosphorous copper anode has a black film which has a thickness of 1000 μm or less and which has one of copper phosphide and copper chloride as a principle component.
13. A phosphorous copper anode according to claim 9 , wherein said phosphorous copper anode has a phosphorous content of 50 to 2,000 wt ppm.
14. A phosphorous copper anode according to claim 9 , wherein said phosphorous copper anode has a black film which has a thickness of 1000 μm or less and which has one of copper phosphide and copper chloride as a principle component.