| AVS 63rd International Symposium & Exhibition | |
| Plasma Science and Technology | Tuesday Sessions |
| Session PS-TuM |
| Session: | Plasma Diagnostics, Sensors and Control |
| Presenter: | Julian Schulze, West Virginia University |
| Authors: | J. Schulze, West Virginia University B. Berger, Ruhr-University Bochum, Germany S. Brandt, West Virginia University B. Bruneau, Ecole Polytechnique, Palaiseau, France Y. Liu, Dalian University of Technology I. Korolov, Hungarian Academy of Sciences A. Derzsi, Hungarian Academy of Sciences E. Schuengel, West Virginia University M. Koepke, West Virginia University T. Mussenbrock, Ruhr-University Bochum, Germany E.V. Johnson, Ecole Polytechnique, Palaiseau, France T. Lafleur, Ecole Polytechnique, Palaiseau, France J.-P. Booth, Ecole Polytechnique, Palaiseau, France D. O'Connell, University of York, UK T. Gans, University of York, UK YN. Wang, Dalian University of Technology Z. Donko, Hungarian Academy of Sciences |
| Correspondent: | Click to Email |
The spatio-temporal dynamics of charged particles and the formation of ion energy distribution functions (IEDF) are investigated in electronegative capacitive RF plasmas operated in CF4 based on a combination of experiments, PIC simulations, and models. In the experiment, Phase Resolved Optical Emission Spectroscopy is used to access the space and time resolved electron dynamics. The DC self bias and IEDFs are measured at the electrodes. For a single frequency discharge operated at 13.56 MHz and 80 Pa we demonstrate that the presence of an electronegative gas can change the electron power absorption dynamics completely compared to electropositive gases by inducing a heating mode transition. Reducing the driving frequency results in the formation of stable striations of the optical emission and electron impact excitation rate due to the collective response of positive and negative ions to the driving frequency. Based on this fundamental understanding, we show that tailoring the driving voltage waveform using a superposition of multiple consecutive harmonics of a fundamental frequency with individually adjustable harmonics’ amplitudes and phases allows for control of the DC self bias, the shape and mean energy of the IEDF, the electron power absorption dynamics, and the spatial division of the discharge into two halves of strongly different electronegativity.