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Explain Recent Development
written 8.1 years ago by | modified 8.1 years ago by |
Mumbai University > Electronics Engineering > Sem 8 > MEMS Technology
Marks: 5M
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written 8.1 years ago by | modified 8.1 years ago by |
Mumbai University > Electronics Engineering > Sem 8 > MEMS Technology
Marks: 5M
written 8.1 years ago by |
Popular sidewall protecting materials:
Sidewall protection materials | Selectivity ratio | Aspect ratio A/P |
---|---|---|
Polymer | 30:1 | |
Photoresists | 50:1 | 100:1 |
Silicon dioxide | 120:1 | 200:1 |
Wet Vs. Dry Etching
Parameters | Dry etching | Wet etching |
---|---|---|
Directionality | Good for most materials | Only with single crystal materials (aspect ratio up to 100) |
Production-automation | Good | Poor |
Environmental impact | Low | High |
Masking film adherence | Not as critical | Very critical |
Selectivity | Poor | Very good |
Materials to be etched | Only certain materials | All |
Process scale up | Difficult | Easy |
Cleanliness | Conditionally clean | Good to very good |
Critical dimensional control | Very good (< 0.1µm) | Poor |
Equipment cost | Expensive | Less expensive |
Typical etch rate | Slow (0.1 µm/min) to fast (6µm/min) | Fast (1µm/min and up) |
Operational parameters | Many | Few |
Control of each rate | Good in case of slow etch | Difficult |