Patent ID: 6734096
Filing Date: 2004-05-11
Classification: H01L

Abstract:
A method for forming a metal pattern in a substrate, the method comprising the steps of:depositing a lower hardmask layer on the substrate, the lower hardmask layer having a dielectric constant less than about 4.5; depositing a middle hardmask layer on the lower hardmask layer; depositing a top hardmask layer on the middle hardmask layer using a vapor deposition process, the top hardmask layer having a thickness less than about 200 Ã¥; forming a first opening in the top hardmask layer in accordance with a first pattern, thereby exposing a portion of the middle hardmask layer; forming a second opening in said portion of the middle hardmask layer in accordance with a second pattern and a corresponding opening in the lower hardmask layer, thereby exposing a portion of the substrate; forming an opening in the substrate; depositing metal in the opening in the substrate; and removing the top hardmask layer, wherein the top hardmask layer is of a material selected from the group consisting of refractory metals, refractory metal nitrides, refractory metal alloys, doped amorphous silicon and doped silicon.