Deep-UV reflection control for patterning dielectric layers

• Published in: Proceedings of SPIE Vol. 3334; no. 1; pp. 356 - 370
• Main Authors: Subramanian, Ramkumar, Bains, Gurjeet S, Lyons, Christopher F, Singh, Bhanwar, Gallardo, Ernesto
• Format: Conference Proceeding
• Language: English
• Published: Bellingham WA SPIE 29.06.1998
• Subjects: Applied sciences; Electronics; Exact sciences and technology; Microelectronic fabrication (materials and surfaces technology); Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Resist; Dielectric materials; Lithography; Antireflection coating; Integrated circuit
• ISBN: 9780819427793; 0819427799
• ISSN: 0277-786X
• DOI: 10.1117/12.310765

This paper describes the results of CD control studies on a dielectric layer that has both dense & isolated trenches and dense contact holes. Both top and bottom anti-reflective coatings were explored as well as the standard process without ARC. All wafers had a standard logic technology process flow and had been through Chemical-Mechanical Planarization prior to patterning. Stepper exposure conditions were varied in the form of partial coherence to obtain maximum depth of focus and exposure latitude. The results of this study were characterized in the form of a CD process window in which Exposure Dose was plotted vs. Defocus for all the 3 patterns i.e. dense & isolated trenches and dense contact holes. The effect of BARC etch was also explored.