The behaviour of aluminium during anhydrous hydrofluoric acid (HF) vapour etching of silicon dioxide films deposited by different methods was studied. Silicon dioxide films were grown by plasma-enhanced chemical vapour deposition (PECVD), low-pressure chemical vapour deposition (LPCVD), and a thermally oxidizing method. The etch rate of different oxides varies a lot. Etching of PECVD oxide causes residues on the aluminium surface as LPCVD and thermal oxide do not. The origin of the residues and different preventative methods are proposed.
- HF vapour
- sacrificial oxide etch
- silicon dioxide
- hydrofluoric acid
Ritala, H., Kiihamäki, J., & Heikkilä, M. (2010). Studies on aluminium corrosion during and after HF vapour treatment. Microelectronic Engineering, 87(3), 501-504. https://doi.org/10.1016/j.mee.2009.07.005