Patent ID: 6806203
Filing Date: 2004-10-19
Classification: H01L

Abstract:
A method of forming a dual damascene structure on a substrate having a dielectric layer already formed thereon, said method comprising:depositing a first hard mask layer over the dielectric layer; depositing a second hard mask layer on the first hard mask layer, wherein said second hard mask layer is an amorphous silicon layer; and completing formation of the dual damascene structure by: (i) using a photoresist layer patterned according to a metal wiring pattern to transfer the metal wiring pattern into said amorphous silicon layer while stopping on said first hard mask layer; (ii) thereafter and prior to etching through said first hard mask layer, depositing a second photoresist layer over the substrate and patterning the second photoresist layer according to a via pattern; (iii) using said second photoresist layer to transfer a via pattern in said dielectric layer and (iv) filling etched portions of the damascene structure with a conductive material.