Electron beam energy distribution in a pulsed-inductively discharge with DC-biased grids*

An electron beam energy distribution is investigated in a pulsed-inductively coupled plasma with DC-biased grids. When the grid is negatively biased, the electrons are accelerated by the potential difference between the grid potential and the plasma potential below the grid. The electron beam energy distribution is measured at 0.8 μs intervals using a Boxcar averaging method with a single Langmuir probe. It is found that the electron beam energy distribution in the afterglow of the pulse period is narrower compared to that in the activeglow. This is because the width of the electron beam energy distribution is dependent to the electron temperature of the plasma above the grid. Additionally, the energy of the electron beam increases right after the afterglow due to the diffusion of the high energy electrons in plasma above the grid.