Sensitive measurements of electric field distributions in low-pressure Ar plasmas by laser-induced fluorescence-dip spectroscopy

Laser-induced fluorescence-dip (LIF-dip) spectroscopy of Ar was used for measuring the distributions of sheath electric fields in low-pressure, inductively-coupled Ar plasmas. A sensitive detection limit of 3 V/cm obtained by LIF-dip allowed the measurement in the presheath region. The distributions of electric fields observed experimentally were compared with those of theoretical calculations based on a simple fluid model. As a result, reasonable agreement between the experiment and the theory was obtained in the electric fields in the sheath region, while the electric fields in the presheath region observed experimentally were higher than the theoretical results. (C) 2004 American Institute of Physics.