| AVS 54th International Symposium | |
| Plasma Science and Technology | Monday Sessions |
| Session PS2+MS-MoM |
| Session: | Plasma Etching for Advanced Interconnects I |
| Presenter: | C.B. Labelle, AMD, Inc. |
| Authors: | C.B. Labelle, AMD, Inc. J. Arnold, IBM Research H. Wendt, Infineon Tech. R.P. Srivastava, Chartered Semicon. Mfg Ltd. K. Kumar, IBM Microelectronics Y. Choi, IBM Microelectronics H. Yusuff, IBM Microelectronics S. Molis, IBM Microelectronics C. Parks, IBM Microelectronics C. Dziobkowski, IBM Microelectronics M. Chace, IBM Microelectronics A. Passano, IBM Microelectronics L. Tai, IBM Microelectronics D. Kioussis, AMD, Inc. J. Yamartino, IBM Microelectronics D. Restaino, IBM Microelectronics L. Nicholson, IBM Microelectronics |
| Correspondent: | Click to Email |
Porous ultra low k dielectrics (k < 2.5) are being integrated into current and future technology nodes. A large focus of the integration of these films has been on the sensitivity of the films to compositional modification (i.e., carbon depletion) during resist strip in the dual damascene patterning scheme. As porous ultra low k dielectric strip processes have evolved and matured, new sensitivities have emerged which affect successful integration. This paper will discuss a case where, in a via-first-trench-last dual damascene integration scheme, the plasma chemistry used during via etch has been found to affect the profiles after trench etch when etching porous ultra low k dielectrics ("ULK via/trench interaction"). Modifications to the via etch plasma chemistry can be made to bring the trench profile back to target, but repeatability of the success of these workarounds is key. Variability in the film composition through the bulk of the film can also instigate post-etch profile changes or exacerbate the etch plasma-induced via/trench interaction. Data will be shown demonstrating the sensitivity of the etch processes to film composition variability. Possible mechanisms for the ULK via/trench interaction will also be discussed.