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arXiv · 1710.11254

Spatial symmetry breaking in single-frequency CCP discharge with transverse magnetic field

Sarveshwar Sharma·Igor Kaganovich·Alexander Khrabrov·Predhiman Kaw·Abhijit Sen
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Abstract

An independent control of the flux and energy of ions impacting on an object immersed in a plasma is often desirable for many industrial processes such as microelectronics manufacturing. We demonstrate that a simultaneous control of these quantities is possible by a suitable choice of a static magnetic field applied parallel to the plane electrodes in a standard single frequency capacitively coupled plasma device. Our particle-in-cell simulations show a 60% reduction in the sheath width (that improves control of ion energy) and a four fold increase in the ion flux at the electrode as a consequence of the altered ion and electron dynamics due to the ambient magnetic field. A detailed analysis of the particle dynamics is presented and the optimized operating parameters of the device are discussed. The present technique offers a simple and attractive alternative to conventional dual frequency based devices that often suffer from undesirable limitations arising from frequency coupling and electromagnetic effects.

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Sarveshwar Sharma, Igor Kaganovich, Alexander Khrabrov, Predhiman Kaw, Abhijit Sen. 2018-07-31. Spatial symmetry breaking in single-frequency CCP discharge with transverse magnetic field. https://doi.org/10.1063/1.5033350

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