| AVS 61st International Symposium & Exhibition | |
| Plasma Science and Technology | Thursday Sessions |
| Session PS2+TF-ThM |
| Session: | Atomic Layer Etching (ALE) and Low-Damage Processing |
| Presenter: | Paul Moroz, Tokyo Electron US Holdings |
| Correspondent: | Click to Email |
Atomic layer etching (ALE) and atomic layer deposition (ALD) are becoming more attractive processing methods primarily due to their higher control of profiles and less induced damage to materials. They require multi-step processing, with each time-step having its own chemistry, incoming fluxes, and energy distribution of species. In this work, we simulated ALE of Si by employing a cycle of two main steps: chlorination of Si surface layer by Cl2 gas and then removal of the chlorinated layer with Ar neutral beam of low energy and narrow energy spectrum, so the sputtering of Si could be neglected. Feature scale simulator FPS3D [1,2] is well designed for the multi-step operations and allowed us to replicate main results of the corresponding experiments [3]. Each step in ALE processing was self-limiting, and we have used the same conditions and parameters as reported for the experiment. The intermediate gas-purge steps were excluded, as simulations allow instantaneous change of chemistry and fluxes, which is not possible in actual processing. We will demonstrate simulation of ALE processing with clear time resolution of chlorination and removal steps and with etch rate corresponding to experiments.
[1] P. Moroz, IEEE Transactions of Plasma Science, 39 (11) 2804 (2011).
[2] P. Moroz, D.J. Moroz, ECS Transactions, 50(46) 61 (2013).
[3] J.K. Kim, et al, J. Vac. Sci. Tech. A 31, 061310 (2013).