Directional deposition of Cu into semiconductor trench structures using ionized magnetron sputtering

摘要: The primary metallization technique in the semiconductor industry for past decade has been magnetron sputtering. general trend towards damascene processing requires capability to fill trenches and vias with sub‐one‐half micron widths aspect ratios (AR) as high 3:1. At these dimensions geometries, angular distribution of sputtered atoms results production voids during deposition. A new approach this problem is directional sputter deposition, where neutrals generated from sputtering are ionized through an inductively coupled rf plasma accelerated substrate via a small dc bias on substrate, causing significant portion flux arrive at normal incidence. experimental parameters process have explored by depositingCu patterned Si wafers. varying effects morphology deposited layer, which indicate relationships between ion‐to‐neutral ratio, total flux, average ion energy. deposition used successfully 600 nm width 1.1 AR Cu near room temperature, appears be extendable more aggressive dimensions.