1:30 PM - 3:30 PM
▲ [7p-PA3-8] Ignition Characteristics of Atmospheric 13.56 MHz RF Inductively Coupled Plasma
Keywords:Inductively Coupled Plasma (ICP), atmospheric plasma, RF plasma
Power efficiency is crucial in the performance of inductively coupled plasma (ICP). Low power efficiency caused by decreased mutual inductance between the coil and plasma results in resistive copper loss leading to high current flow and low electron density. Several ways to increase power efficiency are done including minimizing reflected power through matching networks and optimization of coil diameter. Coil diameters of 1.0-3.0 mm were used in the ignition of atmospheric ICP operated using 13.56 MHz RF generator, 5 mm discharge diameter, 1 mm thick quartz dielectric window, air swirl gas coolant, and working gas using 4 L/m Argon (shown in Figure 1). Reflected power was minimized using built-in impedance matching network of the generator. The input power to ignite the plasma using different coil diameters is shown in Figure 2. Also shown is the minimum power to sustain the plasma and the minimum reflected power measured for each coil diameter. When using coil diameters less than or equal to the dielectric window (1 mm), the ignition and sustaining power is high due to poor field penetration into the plasma region. The optimum ignition and sustaining power was attained using coil diameter of 2 mm. The reflected power was also observed to be lowest at this coil diameter.