Etch selectivity
Etch selectivity is the target material's etch rate divided by that of a comparison material.
Other learning contexts (6)
In context
Under the same conditions, selectivity for a material pair is high if the target layer is removed rapidly while the mask or underlying layer is removed slowly. Always specify the two materials and their comparison order.
Example
If the target film loses 100 nm per minute and the mask loses 10 nm per minute, target-film-to-mask selectivity is 10. The ideal estimated mask consumption for removing 200 nm of target film is 20 nm.
Key distinction
Selectivity estimates consumption of material to retain; do not omit the material pair.
Explore this field
View map ↗22 planned packsView packs ↗
L0 OverviewL1 FoundationsL2 Advanced
