Title |
The study on improving the electric field uniformity in large scale VHF-CCP reactors |
Authors |
구교욱(Kyo-Woog Koo) ; 김일중(Il-Jung Kim) ; 구경완(Kyung-Wan Koo) |
DOI |
https://doi.org/10.5370/KIEE.2020.69.1.211 |
Keywords |
CCP; Standing Wave; Edge Effect; VHF |
Abstract |
Large area PECVD processes have been evolved from HF to VHF technology. The larger the substrate and the higher the frequency, the stronger the standing wave is created at the center of the electrode. In this paper, a seven steps of design process were proposed to improve the standing waves by the shape deformation of electrode concave structure. Sheath thickness of 2 mm and cutting depth of 3.4 mm were simulated under the conditions of circular electrode of 1.1 m diameters, excitation frequency of 40.68MHz and gap of electrode 15mm at 4Torr. The non-uniformity was improved from 9.9%. to 1.1% adapting the processes. The same method was applied to the rectangular electrode to improve the electric field uniformity by cutting the upper electrode by making a mock up in proportion to the processing depth in the direction of the center axis using electric field analysis. |