Spatially Resolved Measurement of Oxygen ICP and CCP Using Optical Emission Spectroscopy with Tomographic Analysis

Spatially resolved measurement of inductively coupled plasma (ICP) and capacitively coupled plasma (CCP) oxygen discharges were performed using tomographic optical emission spectroscopy (OES). Reconstructed O 777.34 nm and 844.65 nm excited-state number densities, and a self-consistent actinometry–collisional radiative model (CRM) method provided the spatial distributions of dissociation degree, electron temperature T e and electron density n e. The ICP showed center-high excitation, center-high dissociation, center-high electron temperature, and center-low electron density. Meanwhile, the CCP exhibited lower excitation, asymmetric dissociation, center-high electron temperature, and high electron density near the periphery. These results reveal differences in power deposition between oxygen ICP and CCP.