| AVS 63rd International Symposium & Exhibition | |
| Thin Film | Wednesday Sessions |
| Session TF+EM+MI-WeA |
| Session: | Thin Films for Microelectronics |
| Presenter: | Weiyi Li, University of Wisconsin-Madison |
| Authors: | W. Li, University of Wisconsin-Madison D. Pei, University of Wisconsin-Madison X. Guo, University of Wisconsin-Madison M.-K. Cheng, University of Wisconsin-Madison S. Lee, University of Wisconsin-Madison Q. Lin, IBM Research Division, T.J. Watson Research Center S.W. King, Intel Corporation J.L. Shohet, University of Wisconsin-Madison |
| Correspondent: | Click to Email |
The effects of cesium (Cs) ion-implantation on uncured plasm a-enhanced chemical-vapor-deposited (PECVD) organosilicate low dielectric constant (low-k) (SiCOH) films have been investigated and compared with the effects of ultraviolet (UV) curing. The mechanical properties, including the elastic modulus and hardness, of the films were improved by up to 30% with Cs implantation, and further up to 52% after annealing at 400°C in a N2 ambient for one hour. These improvements in mechanical properties are either comparable with or better than the effects of UV-curing. These improvements are attributed to an enhancement of the Si-O-Si network structure. The k-value of the SiCOH films increased slightly after Cs implantation, and increased further after annealing. These increases are attributed to two carbon-loss mechanisms, i.e. the carbon loss due to Si-CH3 bond breakage from implanted Cs ions, and the carbon loss due to oxidation during the annealing. The time-zero dielectric breakdown strength was improved after the Cs implantation and the subsequent annealing, and were shown to be better compared with the UV-cured SiCOH films. Within the investigated range of implantation dose, an optimal dose can be found to achieve the best effects. These results indicate that Cs ion implantation has the potential to be a supplement to or a substitution for the incumbent UV curing method for processing SiCOH low-k films.
This work was supported by the Semiconductor Research Corporation under Contract 2012-KJ-2359.
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