Multilayer hardmask scheme for damage-free dual damascene processing of SiCOH dielectrics

• Main Authors: FULLER NICHOLAS C. M, GATES STEPHEN MCCONNELL, DALTON TIMOTHY J
• Format: Patent
• Language: English
• Published: 12.10.2010
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

Interconnect structures possessing an organosilicate glass based material for 90 nm and beyond BEOL technologies in which a multilayer hardmask using a line-first approach are described. The interconnect structure of the invention achieves respective improved device/interconnect performance and affords a substantial dual damascene process window owing to the non-exposure of the OSG material to resist removal plasmas and because of the alternating inorganic/organic multilayer hardmask stack. The latter feature implies that for every inorganic layer that is being etched during a specific etch step, the corresponding pattern transfer layer in the field is organic and vice-versa.