\n\tClassOne Technology, Kalispell, Montana, has developed the CopperMax plating chamber, a design that is said to extend bath life by a factor greater than 20. In this chamber, a cation-exchange semipermeable membrane divides the copper bath into two sections, an upper and a lower. The upper section contains all of the additives, and it actively plates the wafer. The lower section of the bath contains the anode that supplies elemental copper \u2014 which is able to travel through the membrane and into the upper section to ultimately plate the wafer.<\/p>\n
\n\tHowever, the membrane prevents additives from traveling down to the anode, where they would break down and form process-damaging waste products. As a result, the CopperMax bath remains much cleaner, and bath life is extended by over 20 times. This increases uptime, enables higher-quality, higher-rate copper plating, and reduces cost of ownership very substantially.<\/p>\n
\n\tClassOne cites actual performance data from a CopperMax pilot installation on a Solstice tool at a Fortune 100 customer. Over a six-month period, the customer tracked its actual production operating costs while using the new chamber for copper TSV, Damascene, and high-rate copper plating. For the three processes with CopperMax, engineers reported that operating costs were reduced between 95.8% and 98.4% compared with previously used conventional plating chambers.<\/p>\n
\n\tClassOne points out that consumables are the largest cost factor in copper plating. Optimizing copper plating generally requires expensive organic additives \u2014 which are consumed very rapidly and need to be replenished frequently.<\/p>\n