What is Hard mask?
A durable mask of nitride, carbon, metal or similar used when photoresist alone cannot survive the etch, for example in deep-hole etching.
Field: Etching
Hard mask in the explanations
Deep etches would consume resist only about 100 nm thick before finishing, so the resist pattern is first transferred into a nitride, oxide or amorphous-carbon layer, which then masks the main etch—a hard mask.
What is a mask of nitride, carbon or similar material calle…If selectivity is insufficient, a thicker mask or a hard mask is used.
If the oxide etch rate is 100 nm/min and the mask is consum…Self-aligned vias retain the trench-patterning hard mask or use materially distinct layers atop the lines so the via etch is confined within the target line's width, preventing connection to neighbors despite misalignment.
Which technique forms vias self-aligned to wiring trenches …
Questions that mention Hard mask (3)
- What is a mask of nitride, carbon or similar material called, used when photoresist alone cannot survive as a mask, such as when etching deep holes?
- 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?
- Which technique forms vias self-aligned to wiring trenches to tolerate misalignment between upper and lower wiring layers?
Related terms
Photoresist 3D NAND Selectivity Overetch Erosion ALE (atomic layer etching) Anisotropic etching Antenna effect ARDE (aspect-ratio-dependent etching) Ashing