{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

MEMS_05 guiren photolithography_resolution_01

MEMS_05 guiren photolithography_resolution_01 - Chapter 1...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 1 Resolution in photolithography
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Depth of focus Latent image must remain in focus through the depth of the resist layer Focus depth (or defocus tolerance) equ. (1.29) DOF = (+/-) k 2 λ /(NA 2 ) Using equ. (1.15) equ. (1.15): R = k 1 λ / (NA) -> DOF = (+/-) k 2 R 2 /(k 1 2 λ ) K 2 A process-dependent constant ~ 0.5
Background image of page 2
Depth of focus In microscopy, small DOF is highly demanded However, in MEMS, larger DOF is disirable High R could cause penalty of DOF reduction: a focused image through a typical 1-1.5 μ m thick resist cannot be achieved Variable NA is available This is a challenge for miniaturization
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon