What is Numerical aperture (NA)?
A value that expresses the range of angles of light a lens can collect. A larger NA gives higher resolution.
Field: Lithography
Numerical aperture (NA) in the explanations
From the Rayleigh equation R = k1·λ/NA, resolution improves with shorter wavelength λ, larger numerical aperture NA and lower k1.
Based on the resolution formula R = k1 × λ / NA, how can re…Depth of focus is DOF = k2·λ/NA², inversely proportional to NA squared, so raising NA shrinks it rapidly—to around 100 nm in leading-edge lithography.
How does the depth of focus (DOF) generally change when the…High NA means steep incidence angles—about 70° in water at NA 1.35.
In immersion lithography with very high numerical aperture …
Questions that mention Numerical aperture (NA) (12)
- Based on the resolution formula R = k1 × λ / NA, how can resolution be improved (R made smaller)?
- How does the depth of focus (DOF) generally change when the numerical aperture (NA) of an exposure tool is increased?
- Which correctly describes the factor k1 in the resolution formula R = k1 × λ / NA?
- In immersion lithography with very high numerical aperture (NA), why does light polarization need to be considered?
- In a PN junction where the p side is far more heavily doped than the n side (a p+n junction), how does the depletion layer spread?
- How does the built-in (diffusion) potential of a PN junction relate to the doping on each side?
- What is the state of the junctions when a bipolar transistor is in the cutoff region (off)?
- Which correctly describes the flat-band voltage of a MOS structure?
- What material is used for the blue-violet semiconductor laser of about 405 nm that reads and writes Blu-ray discs?
- Which correctly describes ArF immersion lithography?
- Which correctly describes 'High-NA EUV', developed as the next-generation EUV exposure tool?
- Which company is effectively the sole supplier of EUV lithography tools?
Related terms
Depth of focus (DOF) Immersion lithography Multiple patterning CMP Process window OPC (optical proximity correction) Depletion layer Built-in potential Cutoff region Flat-band voltage