Lam Research Corporation
Removal of electroplating bath additives

Abstract:

An example electroplating method comprises feeding fresh electrolyte solution into a bath reservoir via a first inlet of the bath reservoir, and bleeding used electrolyte solution out of the bath reservoir via first outlet of the bath reservoir. Recycled electrolyte solution is received into the bath reservoir via a second inlet of the bath reservoir, and electrolyte solution is discharged from the bath reservoir via a second outlet of the bath reservoir. By-products generated by a plating cell are extracted using an extraction column. A first particle filter is disposed in a fluid pathway between the second outlet of the bath reservoir and the inlet of the plating cell, and a second particle filter is disposed in a fluid pathway between the outlet of the extraction column and the second inlet of the bath reservoir. Flow control means are disposed between the plating cell and the bath reservoir and selectively return a portion of the electrolyte solution to the bath reservoir without passing the returned portion through the first or second filter.