AVS 54th International Symposium | |
Plasma Science and Technology | Thursday Sessions |
Session PS-ThP |
Session: | Plasma Science and Technology Poster Session |
Presenter: | A. Ranjan, University of Houston |
Authors: | A. Ranjan, University of Houston L. Chen, Tokyo Electron U.S. Holdings D.J. Economou, University of Houston V.M. Donnelly, University of Houston |
Correspondent: | Click to Email |
A biased electrode immersed in a plasma has been used to control the plasma parameters by various researchers. For example, Coburn and Kay1 and Xu et al2 inserted a separate positively biased electrode into a plasma, to control the plasma potential, and the energy distribution of ions extracted from the plasma. Here, we report the effects of applying a high negative DC bias voltage on an electrode immersed in an inductively coupled plasma. Plasma properties with the DC voltage ON and OFF were measured using a Langmuir Probe. Superposition of a high negative DC voltage was found to change the electron energy distribution function (EEDF) and the plasma density significantly. Plasma density increased by 25%-250% by the application of high DC voltage of -900 V at 100 mTorr and rf power of 2000-800 W. These changes can have dramatic effects on plasma chemistry. It is expected that this imposed DC bias technique will provide an additional variable to control the etch rate and pattern profile in microelectronics fabrication.
1J. W. Coburn and E. Kay, J. Appl. Phys., 43, 4965 (1972).
2L. Xu, D. J. Economou, V. M. Donnelly and P. Ruchhoeft, Appl. Phys. Lett., 87, 041502 (2005).