Understanding time-resolved processes in atomic-layer etching of ultra-thin Al{sub 2}O{sub 3} film using BCl{sub 3} and Ar neutral beam
- Department of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of)
We scrutinize time-resolved processes occurring in atomic-layer etching (ALET) of ultra-thin Al{sub 2}O{sub 3} film using BCl{sub 3} gas and Ar neutral beam by employing density functional theory calculations and experimental measurements. BCl{sub 3} gas is found to be preferentially chemisorbed on Al{sub 2}O{sub 3}(100) in trans form with the surface atoms creating O-B and Al-Cl contacts. We disclose that the most likely sequence of etching events involves dominant detachment of Al-associated moieties at early etching stages in good agreement with our concurrent experiments on tracking Al{sub 2}O{sub 3} surface compositional variations during Ar bombardment. In this etching regime, we find that ALET requires half the maximum reaction energy of conventional plasma etching, which greatly increases if the etching sequence changes.
- OSTI ID:
- 22311034
- Journal Information:
- Applied Physics Letters, Vol. 105, Issue 9; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Temperature dependence on dry etching of Al{sub 2}O{sub 3} thin films in BCl{sub 3}/Cl{sub 2}/Ar plasma
Electron cyclotron resonance plasma etching of AlGaN in Cl{sub 2}/Ar and BCl{sub 3}/Ar plasmas