PPT Slide
CHEN435/PHGN435: Interdisciplinary Silicon Processing Laboratory
Source
- Product of both RCA cleans
- RCA 1 leave bad oxide (OH groups), RCA2 leaves good oxide
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Solutions
- Dilute HF (HF/H2O)
- BOE Buffered Oxide Etch (HF, NH4F, H2O)
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Mechanism
- Fluorinate silicon to make it water soluble
- Reaction: SiO2 + 4HF => SIiF4 + 2H2O
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Characteristics
- Leaves Si hydrogen terminated - Hydrophobic
- SiO2 is hydrophilic
- Surface susceptible to organics, particulates