Plasma Properties of Superimposed Dual Frequency Inductively Coupled Plasma Source

Plasma characteristics of internal linear inductively coupled plasma sources using dual frequency composed 2 and 13.56 MHz were investigated. Improved plasma characteristics such as higher plasma density, lower electron temperature, and plasma non-uniformity were observed with the dual frequency. Therefore, by using the dual frequency to the U-shaped ICP source, not only the plasma density but also plasma uniformity could be improved in addition to the decrease of possible damage to the substrate.