Generation of nearly uniform oxygen radicals using Rogowski profile electrodes in a capacitively coupled plasma reactor

Abstract

Radicals are widely used for thin film fabrication in semiconductor industries and they can be generated in a capacitively coupled plasma (CCP) reactor. However, edge effects in a conventional CCP reactor with two parallel planar disk electrodes will produce a very nonuniform radical density distribution, especially in the radial direction, leading to seriously negative effects in the manufactured thin films. Furthermore, the strong electric field at the edges of the planar disk electrodes increases the probability of arcing, which may lead to electrode erosion and contamination in the semiconductor manufacturing process. To solve these problems, we employed the Rogowski profile electrodes in a CCP reactor and investigated its performance. Oxygen radicals were produced in the radio frequency-powered CCP reactor with the Rogowski profile electrodes and their spatial distribution of 777 nm photon emission profile was measured using the optical emission spectroscopy as a representative indicator of radical generation. The result shows that the Rogowski profile electrodes can improve the radial uniformity of the radicals while simultaneously reducing the risk of electrical arcing, compared with conventional planar disk electrodes. © 2026 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved. This article is available under the terms of the IOP-Standard License.