| AVS 63rd International Symposium & Exhibition | |
| Plasma Science and Technology | Monday Sessions |
| Session PS+AS+SS-MoA |
| Session: | Plasma Surface Interactions |
| Presenter: | Yoshihide Kihara, Tokyo Electron Miyagi Limited, Japan |
| Authors: | Y. Kihara, Tokyo Electron Miyagi Limited, Japan T. Hisamatsu, Tokyo Electron Miyagi Limited, Japan T. Oishi, Tokyo Electron Miyagi Limited S. Ogawa, Tokyo Electron Miyagi Limited H. Watanabe, Tokyo Electron Miyagi Limited A. Tsuji, Tokyo Electron Miyagi Limited, Japan M. Honda, Tokyo Electron Miyagi Limited, Japan |
| Correspondent: | Click to Email |
In the recent years continuous scaling has required the use of multiple mask patterning technologies such as double and quadruple patterning, and increasingly thin EUV mask films are being planned to be used in the near future. In the patterning process, the fabrication of multilayer films requires the precision of atomic layer level accuracy (within nm level). Some critical challenges that patterning schemes face includes thinning of mask materials, reduction of ARDE related CD-loading, and reduction of LER and LWR. This requires the realization of highly selective etch processes that can address the challenges without trade-offs in other process specifications.
One method to increase the mask selectivity to enable mask thinning, which is one of the major patterning issues, Si-ARC is etched in a depositing condition which protects the resist mask surface, utilizing the material difference between the mask material and the antireflective layer (Si-ARC). However, to enhance selectivity, extra amount of the deposition can be generated. The amount of deposition flux fluctuates depending on the pattern density, leading to CD loading. In order to solve the tradeoff between selectivity and loading, we have proposed a Quasi- Atomic Layer Etching (Quasi-ALE) which is a modification of ALE to employ thin-film adsorption and activation by low ion energy [1]. In this paper, Quasi-ALE is applied to Si-ARC etch step to address three challenges; high selectivity, pattern-independent CD-loading, and vertical etch profiles.
We have also proposed the combination of ALD with etch as CD-loading-free CD control technique [2]. By combining ALD and Quasi-ALE, excellent CD controllability was achieved to address the entire patterning process issues without tradeoffs. In the presentation, various merits of the Fusion Process, which is a combination of Quasi-ALE and ALD, in patterning process, will be introduced. Fusion Process has a significant potential to solve critical challenges in the patterning process of N7, N5 and beyond.
Reference
[1] A.Tsuji et al., AVS 62nd Int. Symp. (2015)
[2] T.Hisamatsu et al., AVS 62nd Int. Symp. (2015)