Radial dependence diagnosis of inductively coupled Ar plasma based upon optical emission spectroscopic measurement with spectral reflectance compensation

Yuya Yamashita; Kenta Doi; Tetsuji Kiyota; Keiichiro Asakawa; Sotaro Hosoya; Wataru Kikuchi; Atsushi Nezu; Hiroshi Akatsuka

doi:10.1063/5.0138912

Radial dependence diagnosis of inductively coupled Ar plasma based upon optical emission spectroscopic measurement with spectral reflectance compensation

Rev Sci Instrum. 2023 Aug 1;94(8):083503. doi: 10.1063/5.0138912.

Authors

Yuya Yamashita¹, Kenta Doi², Tetsuji Kiyota³, Keiichiro Asakawa², Sotaro Hosoya¹, Wataru Kikuchi¹, Atsushi Nezu^{4

5}, Hiroshi Akatsuka^{1

5}

Affiliations

¹ Department of Electrical and Electronic Engineering, School of Engineering, Tokyo Institute of Technology, 2-12-1-N1-10 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
² Institute of Advanced Technology, ULVAC, Inc., 1220-1 Suyama, Susono-shi, Shizuoka 410-1231, Japan.
³ Strategic Planning Department, ULVAC, Inc., 2500 Hagisono, Chigasaki-shi, Kanagawa 253-8543, Japan.
⁴ Safety and Radiation Management Division, Open Facility Center, Tokyo Institute of Technology, 2-12-1-N1-10 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.
⁵ Laboratory for Zero-Carbon Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1-N1-10 Ookayama, Meguro-ku, Tokyo 152-8550, Japan.

PMID: 38065137
DOI: 10.1063/5.0138912

Abstract

This study proposed a simple method to evaluate the spectral reflectance of the inner wall of a vacuum chamber. A method for calculating spectral emission coefficients by taking the spectral reflectance of the chamber inner wall into account was proposed. Furthermore, plasma diagnosis based on optical emission spectroscopic (OES) measurement was performed so as to obtain radial dependence of electron temperature Te and density Ne of a radio frequency inductively coupled Argon (Ar) plasma by applying a collisional-radiative model to radially resolved emission spectra of the Ar plasma assuming axial symmetry. In addition, Langmuir probe measurement and electromagnetic simulation were performed and compared with the OES-based plasma diagnosis results. The spectral radiance compensation improved the diagnostic result by 0.6% and 3.1% for Te and Ne, respectively.