Superconformal filling of submicrometer trenches was achieved using substrates that were catalyzed with KSeCN prior to metal deposition in a catalyst-free, silver-cyanide electrolyte. The degree of superfill was dependent on the time the specimen spent in the KSeCN-containing solution prior to electrodeposition. Longer derivatization times correspond to higher initial catalyst coverages. The feature filling results were consistent with the curvature enhanced accelerator coverage mechanism of superconformal deposition. This mechanism implies that area changes during deposition in a feature lead to higher catalyst coverage at the bottom of the feature, thus enhancing the deposition rate and allowing bottom-up fill. (C) 2003 The Electrochemical Society.