CVS Cyclic Voltametric Stripping

Nova’s chemical metrology products utilize cyclic voltametric stripping (CVS) technology. CVS is an electrochemical method for measuring the concentration of organic additives in galvanic plating baths to deposit metals or alloys for interconnects and bumps, on wafer structures. The organic additives are essential for optimizing the plating process and ensuring defect-free metallization.

With CVS techniques, metal is deposited by generating defined potentials between the rotating platinum working electrode (WE) and a reference electrode (RE). Take, for example, the depositing of copper to a rotating platinum electrode followed by dissolving, or stripping, it back into the solution. The charge needed for the depositing process is measured and used for evaluation. The step is repeated several times under different conditions, eventually leading to the organic additive concentration measurement.

Highlights and Benefits

Emulation of the entire plating process, rather than the determination of individual organic components, to consider the impact of all the possible bath ingredients
Patented long-life, maintenance-free reference electrode system
Durable working- and counter-electrodes
Adaptability for myriad copper bath types for front-end, back-end, and PCB usage
Availability for organic additives analyses, in non-copper bath types, such as tin, tin-silver, cobalt, gold, and nickel baths

CVS’ hardware setup can also be used for other voltametric techniques such as: