Patent ID: 7439174
Filing Date: 2008-10-21
Classification: H01L,Y10T

Abstract:
1. A process for damage-free patterning of at least one organosilicate glass interlevel dielectric (OSG ILD) comprising: forming a structure comprising a multilayer hardmask on a surface of an OSG ILD material stack comprising top and bottom OSG ILD layers separated by a buried etch stop layer, said multilayer hardmask comprising an organic material layer selected from diamond like carbon, amorphous carbon and an organic polymer, a first Si-containing inorganic material layer located atop the organic material layer and a second Si-containing inorganic material layer comprising atoms of at least Si, C and H having a dielectric constant between 2.6 and 3.5 beneath the organic material layer, wherein said first Si-containing inorganic layer comprises a stack of at least an oxide overlayer and a nitride underlayer, wherein said oxide overlayer is selected from silicon oxide and an amorphous material comprising Si and O, and said nitride underlayer is selected from SiN, SiON and an amorphous material comprising elements of Si and N; forming a first opening defining a partial line pattern in said oxide overlayer, wherein said first opening exposes a portion of said nitride underlayer; conditioning the exposed portion of said nitride underlayer to prevent resist poisoning, said conditioning comprising an oxygen plasma; forming a second opening defining a via pattern through said exposed portion of the nitride underlayer, said organic material layer and a portion of said OSG ILD; completing the line pattern by removing said nitride overlayer, said organic material layer, and a portion of said OSG ILD that is adjacent to said via pattern; deepening the via pattern though said OSG ILD; and filling said via and line patterns within said OSG ILD with at least a conductive material comprised of Cu.