Highly pure copper anode for electrolytic copper plating, method for manufacturing same, and electrolytic copper plating method

A highly pure copper anode for electrolytic copper plating comprising a grain boundary structure satisfying the following relationship:

• LσN/LN≧0.35, wherein
• (a) a total crystal grain boundary length L within a measurement area being measured with a scanning electron microscope by irradiating an electron beam to individual crystal grains on a surface of the anode under a condition that an interface between crystal grains laying side-by-side having a mutual crystal orientation difference of 15° or more is defined as the crystal grain boundary, and a unit total crystal grain boundary length LN being a converted value corresponding to a unit area of 1 mm2 from the total crystal grain boundary length L;
• (b) locations of special crystal grain boundaries, where a special grain boundary is formed between an interface between crystal grains laying side-by-side, being determined, a total special crystal grain boundary length Lσ of the special crystal grain boundaries being measured with a scanning electron microscope by irradiating an electron beam to individual crystal grains on the surface of the anode, and a unit total special crystal grain boundary length LσN being a converted value corresponding to a unit area of 1 mm2 from the total special crystal grain boundary length Lσ;
• and
• (c) LσN/LN being a ratio of LσN, which is the measured unit total special crystal grain boundary length, to LN, which is the measured unit total crystal grain boundary length.