Co Anode, And Co Electroplating Method Using Co Anode

Abstract

Provided is a novel anode for electroplating, which replaces the Cu anode and which is capable of suppressing plating defects. The Co anode has a number of particles with a grain size of 0.5 μm or more of 6000 particles/g or less, as measured by an in-liquid particle counter according to JIS B 9925 after dissolving the Co anode in dilute nitric acid having a nitric acid concentration of 20% by mass.

1 . A Co anode for electroplating, the Co anode having a number of particles with a grain size of 0.5 μm or more of 6000 particles/g or less, as measured by an in-liquid particle counter according to JIS B 9925 after dissolving the Co anode in dilute nitric acid having a nitric acid concentration of 20% by mass. 
     
     
         2 . The Co anode according to  claim 1 , wherein the number of particles with a grain size of 0.5 μm or more is 5000 particles/g or less. 
     
     
         3 . The Co anode according to  claim 1 , wherein the Co anode has a purity of 3N or more. 
     
     
         4 . The Co anode according to  claim 3 , wherein the purity is 4N or more. 
     
     
         5 . The Co anode according to  claim 3 , wherein the Co anode has a Fe concentration of 10 ppm or less. 
     
     
         6 . The Co anode according to  claim 5 , wherein the Fe concentration is 5 ppm or less. 
     
     
         7 . A Co electroplating method using the Co anode according to  claim 1 . 
     
     
         8 . An evaluation method of Co anode for electroplating, the method comprising the steps of:
 dissolving the Co anode in dilute nitric acid having a nitric acid concentration of 20% by mass,   measuring an in-liquid particle in the dilute nitric acid in which the Co anode is dissolved by an in-liquid particle counter according to JIS B 9925, and   judging good or bad of the Co anode based on the measurement result by the in-liquid particle counter.   
     
     
         9 . The evaluation method of Co anode for electroplating according to  claim 8 , wherein the step of judging good or bad of the Co anode based on the measurement result by the in-liquid particle counter includes:
 a step of evaluating if a number of particles with a grain size greater than or equal to a predetermined grain size of 0.5 μm or more is below a predetermined threshold of 6000 particles/g or less.