| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method and a system which easily and accurately measures and controls a concentration of sulfur compounds in an electroless nickel plating solution. <P>SOLUTION: A concentration control system 1 includes: an electrochemical measurement instrument 4 which includes a working electrode 41 of which at least the surface to be brought into contact with an electroless nickel plating solution L is made of gold, silver, or platinum, a counter electrode 42, a reference electrode 43, a voltage controller 44 for controlling a potential of the working electrode 41 relative to the reference electrode 43, and an ammeter 45 for measuring a current flowing between the counter electrode 42 and the working electrode 43 and measures, by the ammeter, a current I flowing between the working electrode 41 and the counter electrode in accordance with a potential of the working electrode 41 relative to the reference electrode 43 in the electroless nickel plating solution; a controller 5 which calculates a concentration of sulfur-based compounds on the basis of the current I and outputs a control signal S to adjust the concentration of sulfur-based compounds in an electroless nickel plating bath 2; and an adjuster 6 which adjusts the concentration of sulfur-based compounds in the electroless nickel plating bath 2 on the basis of the control signal S. <P>COPYRIGHT: (C)2012,JPO&INPIT |
