PLASMA DIAGNOSIS APPARATUS AND THE SIGNAL PROCESSING METHOD OF THE SAME

摘要

PURPOSE: A plasma diagnosis device and a signal processing method thereof are provided to accurately measure plasma variables including plasma density, an electronic temperature, plasma potential and floating potential by measuring AC inputted from plasma. CONSTITUTION: A driving unit(180) outputs a periodic voltage signal of a driving frequency. A circuit between the driving unit and a probe electrode is comprised of a preliminary equivalent resistor(Rs) and a parasitic capacitor(Cs) which is serially connected to a preliminary equivalent resistor. A parasitic current flows through the parasitic capacitor. A probe electrode(110) and the plasma are comprised of a plasma capacitor and a plasma resistor serially connected to the plasma capacitor. An input current flowing through the driving unit is shown as the vector sum of the plasma current and the parasitic current.