Low-k interconnect structure comprised of a multilayer of spin-on porous dielectrics

摘要

A low-k dielectric metal conductor interconnect structure having no micro-trenches present therein and a method of forming such a structure are provided. Specifically, the above structure is achieved by providing an interconnect structure which includes at least a multilayer of dielectric materials which are applied sequentially in a single spin apply tool and then cured in a single step and a plurality of patterned metal conductors within the multilayer of spun-on dielectrics. The control over the conductor resistance is obtained using a buried etch stop layer having a second atomic composition located between the line and via dielectric layers of porous low-k dielectrics having a first atomic composition. The inventive interconnect structure also includes a hard mask which assists in forming the interconnect structure of the dual damascene-type. The first and second composition are selected to obtain etch selectivity of at least 10 to 1 or higher, and are selected from specific groups of porous low-k organic or inorganic materials with specific atomic compositions and other discoverable quantities.