Similarity of capacitive radio-frequency discharges in nonlocal regimes
Abstract
Similarity transformations are essential for correlating discharges at different scales, which are mostly utilized with local field or local energy approximations. In this work, we report the fully kinetic results from particle-in-cell/Monte Carlo collision simulations that unambiguously demonstrate the similarity of radio frequency (rf) discharges in nonlocal regimes where the electron energy relaxation length is much larger than the gap dimension. It is found that at a constant rf voltage amplitude, discharges will be similar if the gas pressure, inverse of gap distance, and rf driving frequency are all changed by the same scaling factor. The scaling relations of fundamental parameters are illustrated for rf discharges in the alpha-mode with secondary electron emission ignored, and the temporal electron kinetics are shown to have invariance in similar discharges. The results explicitly validate the scaling laws in nonlocal kinetic regimes, indicating promising application potentials of the similarity transformations across a wide range of kinetic regimes.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 01, 2020
- Source ID
- 10.1063/5.0022788
Entities
People
- Bocong Zheng
- John Verboncoeur
- Peng Zhang
- Qi Hua Fan
- Xinxin Wang
- Yangyang Fu
Organizations
- Air Force Office of Scientific Research
- Michigan State University
- National Natural Science Foundation of China
- National Science Foundation
- Tsinghua University
- United States Department of Energy