US Patent 9953811 Plasma processing method

A plasma processing method for performing a plasma process on a processing target substrate is provided. The plasma processing method includes: segmenting a RF antenna into an inner coil, an intermediate coil, and an outer coil with gaps therebetween in a radial direction, respectively, the inner coil, the intermediate coil and the outer coil being electrically connected to one another in parallel between a first node and a second node; providing a variable intermediate capacitor and a variable outer capacitor between the first node and the second node, the variable intermediate capacitor being electrically connected in series to the intermediate coil, the variable outer capacitor being electrically connected in series to the outer coil, no reactance device being connected to the inner coil; and controlling plasma density distribution on the processing target substrate by selecting or variably adjusting electrostatic capacitances of the intermediate capacitor and the outer capacitor.