[18p-A31-1~19] 8.2 Plasma deposition of thin film, plasma etching and surface treatment

5:30 PM - 5:45 PM JST(8:30 AM - 8:45 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation AwardHighlighted Presentation

[18p-A31-16] Analysis of reaction mechanism of SiO₂ film during cryogenic etching using F₂/Ar/H₂ gas plasma

〇Yuma Kato¹, Junji Kataoka¹, Ryo Saito², Daiki Iino¹, Hiroyuki Fukumizu¹, Tetsuya Sato², Kazuaki Kurihara¹ (1.Kioxia Corp., 2.Yamanashi Univ.)

Keywords:

cryogenic etching,silicon dioxide

We carried out in-situ FT-IR analyses of the SiO₂ film surface during etching using F₂/Ar/H₂ gas plasma beams at temperatures ranging from -150 ℃ to room temperature (RT). The etch rate (ER) of the SiO₂ film had the maximum value at the -100 ℃. The amount of H₂O condensing on the SiO₂ surface increased as the temperature decreased from RT to -100 ℃, and the amount of adsorbed HF also increased due to co-adsorption with H₂O. Those increase of H₂O and HF correspond to the increase of the SiO₂ ER. Below -100 ℃, byproduct SiF_x appeared due to its low volatility at such low temperatures, resulting in the ER decrease.