Effects of Bias Power on EEPFs near the Substrate in Argon ICP Measured by a Langmuir Probe

Electron energy probability functions (EEPFs) were measured 12 mm above the substrate across the diameter of the argon ICP chamber using a single Langmuir probe under applied bias power. The EEPFs exhibited reduced low-energy components and enhanced high-energy tails under 12.5 MHz RF bias, evolving toward a one-temperature Maxwellian profile.