Characterization of fundamental plasma parameters in a double inductively coupled plasma: simulation and experiment

A double inductively coupled plasma (DICP) setup is used explicitly in biomedical applications, such as sterilizing microorganisms on large-scale objects. For this purpose, a homogeneous plasma process is required. Hence a spatially resolved characterization of the relevant discharge parameters becomes increasingly essential. This work studies a DICP computationally and compares it to experimental results at the same discharge conditions (f = 13.56 MHz, 100 sccm Ar/O$_2$). The Hybrid Plasma Equipment Model (HPEM) developed by M. Kushner was used for the simulation. The experiment uses multipole resonance probe, optical emission spectroscopy, and tuneable diode laser absorption spectroscopy measurements for the characterization. Parameters like power (50 - 800W), pressure (2 - 20 Pa), and argon/oxygen gas mixture (98/2 - 80/20) are varied, and their influence on the discharge is compared. The focus is on radial profiles such as electron densities and temperatures. It is found that the absolute values and the spatial evolution of experimental and simulated data are in good agreement. In addition, HPEM gives insights into the two-dimensional resolution of the power deposition as well as into the capacitive and inductive coupling of the coils. Furthermore, the radial distribution of reactive species like oxygen, which are necessary for biomedical applications, can be investigated.