Patent ID: 6117781
Filing Date: 2000-09-12
Classification: H01L

Abstract:
A method of forming a layer of an electrically conductive material filling at least one high aspect ratio recess formed in a substrate surface, which method comprises the sequential steps of:forming at least one high aspect ratio recess in a surface of a substrate, said recess comprising:(a) a mouth surface portion at the upper end thereof comprising an opening having a width profile tapering from a first, wider width at said substrate surface to a second, narrower width at a first depth below said substrate surface, said mouth surface portion bordering an adjacent, non-recessed substrate surface portion;(b) an interior wall surface portion of said second, narrower width extending at a substantially constant width from said first depth to a second depth below said substrate surface; and(c) a bottom surface portion at said second depth;forming an electrically conductive nucleation/seed layer over recess surface portions (a), (b), (c), formation of overhanging portions of said nucleation/seed layer at said mouth surface portion (a) being substantially prevented due to the inwardly tapered width profile thereof;filling said recess with a layer of an electrically conductive material by electroplating said layer on the nucleation/seed layer over recess surface portions (a), (b), and (c);whereby at least one of occlusion and pinching off of the recess mouth surface portion (a) during said electroplating due to formation thereon of overhanging portions of said conductive material layer on overhanging portions of said nucleation/seed layer is prevented.