The effect of probe length variation on Plasma parameters

Abstract

This study examines the impact of varying probe length on the measurement of Argon plasma parameters like electron density (𝑛𝑒), electron temperature (𝑇𝑒), plasma potential (𝑣𝑝), and electron energy probability function (EEFP). Argon plasma is generated in MaPE ICP system for investigating the plasma parameters like electron density (𝑛𝑒), electron temperature (𝑇𝑒), plasma potential (𝑣𝑝), and electron energy probability function (EEFP) by employing Langmuir probe with length ranging from 5mm to 10mm. The experiment is conducted under varying RF power (10watt, 30watt, 50watt, 70watt, and 100watt) with constant pressures (1 Pa, 5 Pa and 10 Pa) respectively it is observed that electron density (𝑛𝑒) shows increasing trend as the probe length increases at constant RF power and pressure. It is also observed that electron temperature (𝑇𝑒) initially rises with probe length but gradually decreases beyond 6mm. Plasma potential (𝑣𝑝) decreases with probe length and the highest potential is observed at minimum RF power. Electron Energy Probability Function (EEPF) exhibits a declining trend with increasing energy. By using the Langmuir Probe as primary diagnostic tool, this research highlights the involved relationship between probe length, RF power, and plasma parameters. The results, underscore the significance of considering probe characteristics in plasma diagnostics.