What is Overetch?
Continuing to etch for a set time after endpoint so the film is removed everywhere on the wafer. It is done under conditions with high selectivity to the underlying layer.
Field: Etching
Overetch in the explanations
An overetch—often about 20–50% of the main etch time—ensures complete removal.
After the etch endpoint is detected, what is it called to c…Etching 500 nm of oxide consumes 100 nm of mask, so allowing for overetch and edge erosion the mask should be at least about 150–200 nm thick.
If the oxide etch rate is 100 nm/min and the mask is consum…Remedies include pulsed plasma or low-frequency bias to reduce charging and tuned overetch conditions.
In gate etching, what is the phenomenon called in which the…
Questions that mention Overetch (6)
- After the etch endpoint is detected, what is it called to continue etching for a set time to ensure the film is removed across the whole wafer?
- If the oxide etch rate is 100 nm/min and the mask is consumed at 20 nm/min, what is the selectivity to the mask?
- In gate etching, what is the phenomenon called in which the pattern sidewall is undercut laterally near the boundary with the underlying insulator?
- If etching proceeds at 100 nm/min for 3 minutes, how much film is removed?
- In gate electrode etching, what is commonly done to preserve the thin gate insulator underneath?
- When a 1 µm film is etched just down to the underlayer by perfectly isotropic wet etching, roughly how much is etched laterally from the mask edge (undercut)?
Related terms
Selectivity Erosion Hard mask Plasma Endpoint detection Wet etching Isotropic etching MEMS ALE (atomic layer etching) Anisotropic etching