| AVS 63rd International Symposium & Exhibition | |
| Plasma Science and Technology | Monday Sessions |
| Session PS-MoA |
| Session: | Advanced BEOL/Interconnect Etching |
| Presenter: | Nathan Marchack, IBM Research Division, T.J. Watson Research Center |
| Authors: | N.P. Marchack, IBM Research Division, T.J. Watson Research Center M. Yamazaki, TEL Technology Center, America, LLC Q. Yang, TEL Technology Center, America, LLC N. Joy, TEL Technology Center, America, LLC S.U. Engelmann, IBM Research Division, T.J. Watson Research Center E.A. Joseph, IBM Research Division, T.J. Watson Research Center A. Ranjan, TEL Technology Center, America, LLC |
| Correspondent: | Click to Email |
While numerous processes for generating volatile metal etch products have been established in the field of plasma processing, there remain certain families of elements, e.g. ferromagnetic transition metals and their alloys, which have yet to display similar etch mechanisms. These and similar elements are finding increasing utility in novel memory technologies and thus their patterning at shrinking length scales poses an interesting problem for future technology nodes.
The existence of gas phase organo-metallic precursors such as M[(CO)]x (where M = Ni, Fe, Co, etc.) has piqued curiosity in seeking pathways to generate such species using NH3/CO chemistry in the literature[1], however experimental observation of such byproducts in the gas or plasma phase through techniques such as mass spectrometry has not been reported[2]. Older literature may suggest alternative mechanisms involving the reaction of such metals in the gas phase with linear nitriles[3] and amines[4]. We explore potential reactions of such organic species generated in a variety of high density plasma sources, with a focus on defining how parameters such as source power, type, and gas ratio affect the discharge properties.
The results of this study will then be applied to patterned film stacks of commonly reported metal elements (e.g. Ni, Fe, Co) demonstrating a potential means for etching these materials at tighter pitches (<200nm) for line/space and pillar geometry with reduced sidewall residue and minimal hard mask loss.
References:
[1]: Kubota et al., Journal of Magnetism and Magnetic Materials, 272-276, 2004.
[2]: Jeon et al., Journal of Vacuum Science and Technology A, 33, 061304, 2015.
[3]: Lebrilla et al., Journal of American Chemical Society, 109, 5639-5644, 1987.
[4]: Radecki and Allison, Journal of American Chemical Society, 106, 946-952, 1984.