| AVS 62nd International Symposium & Exhibition | |
| Plasma Science and Technology | Tuesday Sessions |
| Session PS1-TuA |
| Session: | Novel Materials and Etch Chemistry |
| Presenter: | Robert Bruce, IBM Research Division, T.J. Watson Research Center |
| Authors: | R.L. Bruce, IBM Research Division, T.J. Watson Research Center T. Suzuki, ZEON Chemicals L.P. J. Lee, IBM Albany Nanotech Center E.A. Joseph, IBM Research Division, T.J. Watson Research Center S.U. Engelmann, IBM Research Division, T.J. Watson Research Center A. Itou, ZEON Chemicals L.P. M. Nakamura, ZEON Chemicals L.P. G. Matsuura, Zeon Corporation, Kawasaki, Japan J.C. Arnold, IBM Albany Nanotech Center E.M. Sikorski, IBM Research Division, T.J. Watson Research Center |
| Correspondent: | Click to Email |
As the semiconductor industry continues to drive critical dimensions smaller moving to 7nm technology node and beyond, the challenges to dielectric etch for BEOL fabrication become ever greater. Plasma etch using fluorocarbon passivation gas to establish selectivity and maintain straight profiles during pattern transfer has been the mainstay of patterning into dielectrics. We have previously reported the superior performance of etching SiO2 and low-k using the hydrofluorocarbon gas C5HF7, which had greater selectivities and reduced sidewall damage compared to other passivation gases such as C4F8 and C4F6. This was due to the greater deposition behavior of C5HF7 because of fluorine scavenging by intramolecular hydrogen. Using C5HF7, we have fabricated dual damascene structures in various low-k dielectrics ranging from k2.7 to 2.4. In addition, we have recently demonstrated low-k etch at 7nm node with superior profile control compared to C4F8-based etch. In this talk, we investigate the reasons behind the improved etch performance using C5HF7 compared to other passivation gases and potential future applications.