In this work inductively coupled argon plasmas, generated by an external coil, are studied in the low pressure range. The E mode to H mode transition is observed and analysed using the DC self bias potential and the luminous intensities of three argon spectral lines, measured by optical emission spectroscopy. According to our results, during the mode transition the electron density of the plasma suddenly increases, and the average electron energy is higher in the E mode than in the H mode.
