Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
권호 표지

Etching Anisotropy Depending on the SiO2 and Process Conditions of NF3 / H2O Remote Plasma Dry Cleaning

NF3 / H2O 원거리 플라즈마 건식 세정 조건 및 SiO2 종류에 따른 식각 이방 특성

  • 오훈정 (연세대학교 비아이티 마이크로 팹 연구소) ;
  • 박세란 ((주)삼성전자) ;
  • 김규동 ((주)ACN) ;
  • 고대홍 (연세대학교 비아이티 마이크로 팹 연구소)
  • Received : 2023.11.07
  • Accepted : 2023.12.12
  • Published : 2023.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

We investigated the impact of NF3 / H2O remote plasma dry cleaning conditions on the SiO2 etching rate at different preparation states during the fabrication of ultra-large-scale integration (ULSI) devices. This included consideration of factors like Si crystal orientation prior to oxidation and three-dimensional structures. The dry cleaning process were carried out varying the parameters of pressure, NF3 flow rate, and H2O flow rate. We found that the pressure had an effective role in controlling anisotropic etching when a thin SiO2 layer was situated between Si3N4 and Si layers in a multilayer trench structure. Based on these observations, we would like to provide further guidelines for implementing the dry cleaning process in the fabrication of semiconductor devices having 3D structures.

Keywords

Acknowledgement

이 연구 보고서는 정부의 재원으로 전자정보디바이스산업 원천기술개발사업(반도체) (과제번호 10043438) 및 한국연구재단의 기초연구사업(과제번호NRF- 2017R1A 2B2004986)의 지원을 받아 수행되었습니다.

References

  1. https://irds.ieee.org/editions.
  2. S. B. Samavedam et al., "Future Logic Scaling: Towards Atomic Channels and Deconstructed Chips," 2020 IEEE International Electron Devices Meeting (IEDM) Technical Digest, pp. 1.1.1-1.1.10, 2020.
  3. https://www.koreatimes.co.kr/www/tech/2023/08/129_356671.html
  4. K. Kim, "The Smallest Engine Transforming Humanity: The Past, Present, and Future," 2021 IEEE International Electron Devices Meeting (IEDM) Technocal Digest, pp. 1.1.1-1.1.8, 2021.
  5. T. Tanaka, et al., "Mechanism of Resist Pattern Collapse during Development Process", Japanese Journal of Applied Physics, vol. 32, pp. 6059-6064, 1993.
  6. G. W. Gale, "Industry Context for Semiconductor Wet Etch and Surface Preparation", Solid State Phenomena, vol.282, pp. 3-9, 2018. https://doi.org/10.4028/www.scientific.net/SSP.282.3
  7. J.W. Park, et al., "In situ dry cleaning of Si wafer using OF2 / NH3 remote plasma with low global warming potential", Journal of Physics D: Applied Physics, vol. 51, 445201, 2018.
  8. H. Ogawa, et al., "Dry Cleaning Technology for Removal of Silicon Native Oxide Employing Hot NH3/NF3 Exposure", Japanese Journal of Applied Physics, vol. 41, pp. 5349-5358, 2002.
  9. T. Hattori, et al., "Highly Selective Isotropic Gas-Phase Etching of SiO2 using HF and Methanol at Temperatures -30℃ and Lower," Japanese Journal of Applied Physics, vol. 62, pp.SI1001-1-8, 2023.
  10. H. Ohtake, et al., "Isotropic Atomic Layer Etchings of Various Materials by Using Dry Chemical Removal," Japanese Journal of Applied Physics, vol. 62, pp. SG0801-1-12, 2023.
  11. H. J. Oh, et al., "NF3/NH3 Dry Cleaning Mechanism Inspired by Chemical and Physical Surface Modification of Si, SiO2, and Si3N4," ECS Transactions, vol. 61, no. 38, pp. 1-8, 2014. https://doi.org/10.1149/06138.0001ecst
  12. S.-M. Kang, et al., "Study on Etching Selectivity of Oxide Films in Dry Cleaning Process with NF3 and H2O," Solid State Phenomena, vol. 255, pp. 86-90, 2016. https://doi.org/10.4028/www.scientific.net/SSP.255.86
  13. S. Park, et al., "SiGe Surface Changes During Dry Cleaning with NF3/H2O Plasma," Journal of the Semiconductor & Display Technology, vol.19, no.2, pp.45-50, 2020.
  14. W. S. Yang, et al., "A New Surface Modification Method to Prevent the Release-Stiction of Micromechanical Structures During HF Vapor-Phase Etching," Japanese Journal of Applied Physics, vol. 43, pp. 6008-6011, 2004.
  15. B. Radjenovic, et al., "Level Set Approach to Anisotropic Wet Etching of Silicon," Sensors, vol.10, pp.4950-4967, 2010.
  16. R. M. M. Hasan, et al., "Substrate Orientation Effects on Nanoelectrode Lithography: ReaxFF Molecular Dynamics and Experimental Study," Journal of Physics D: Applied Physics, vol.53, p.295108, 2020.