4 ms·

An intriguing answer, but I'm afraid I didn't know enough terms of art to really understand it. Here are some definitions for the interested: ArF: argon fluori

An intriguing answer, but I'm afraid I didn't know enough terms of art to really understand it. Here are some definitions for the interested: ArF: argon fluoride. ArF lasers emit at 193nm EUV (Extreme Ultraviolet Lithography): A type of lithography that uses light with a wavelength of 13nm DUV (Deep Ultraviolet Lithography): Refers to lithography techniques that use deep ultraviolet light, such as 193nm ArF, for patterning. NA (Numerical Aperture): A measure of the light-gathering ability of an optical system, like a lens, used in lithography to improve resolution. Water Immersion: A technique where water is used between the lens and the wafer to enhance resolution in immersion lithography. Multi-patterning: A method where multiple exposures are used to create smaller features. (Would like to know more) Pitch: The distance between identical features in an array, crucial for determining the density of components on a chip. Gate Length: The length of the gate in a transistor - affects its performance and power consumption. Fin-FETs (Fin Field-Effect Transistors): Transistors with a fin-like structure that improve control over current flow, commonly used in advanced nodes. Nano-sheets: a three-dimensional transistor structure that utilizes thin horizontal sheets of semiconductor material stacked vertically. GAA means: "gate all around" - the gate surrounds the channel on all four sides with stacked horizontal nano-sheets.

watersb 3y ago
> Multi-patterning: A method where multiple exposures are used to create smaller features. (Would like to know more) It might be better to start by considering ways to play with shadows cast by a single photolithography mask... The Wikipedia article on "Computational Lithography" is a good place to start: https://en.m.wikipedia.org/wiki/Computational_lithography https://en.m.wikipedia.org/wiki/Computational_lithography A particularly fascinating technique, linked in that article, is the use of "Phase-Shifting Photo Masks": https://en.m.wikipedia.org/wiki/Phase-shift_mask https://en.m.wikipedia.org/wiki/Phase-shift_mask And then there are ways to play with diffraction effects, at the edges of the opaque shapes of the mask: https://en.wikipedia.org/wiki/Optical_proximity_correction https://en.wikipedia.org/wiki/Optical_proximity_correction In addition to diffraction and phase shift patterns, you can create shapes by illuminating the mask and wafer with more than one light source. It may be helpful to consider this "multiple illumination" of a single photo mask in the context of a "double slit" interference pattern: https://en.m.wikipedia.org/wiki/Diffraction_from_slits#Multiple_slits https://en.m.wikipedia.org/wiki/Diffraction_from_slits#Multi... After you've run out of tricks, you have write over the shapes laid down by a single mask, running the wafer through the process with a different mask. I find the current Wikipedia article for multi-patterning to be a bit more difficult to understand, but it's certainly worth the effort. After studying this article a bit, I think it might help to start in the middle of the article, at "Pitch Splitting". A second read of the article, starting at the top, may then provide more context: https://en.wikipedia.org/wiki/Multiple_patterning#Pitch_splitting https://en.wikipedia.org/wiki/Multiple_patterning#Pitch_spli... . (Ironic: the article on Multiple Patterning requires multiple passes!)

watersb 3y ago

> Multi-patterning: A method where multiple exposures are used to create smaller features. (Would like to know more) It might be better to start by considering ways to play with shadows cast by a single photolithography mask... The Wikipedia article on "Computational Lithography" is a good place to start: https://en.m.wikipedia.org/wiki/Computational_lithography https://en.m.wikipedia.org/wiki/Computational_lithography A particularly fascinating technique, linked in that article, is the use of "Phase-Shifting Photo Masks": https://en.m.wikipedia.org/wiki/Phase-shift_mask https://en.m.wikipedia.org/wiki/Phase-shift_mask And then there are ways to play with diffraction effects, at the edges of the opaque shapes of the mask: https://en.wikipedia.org/wiki/Optical_proximity_correction https://en.wikipedia.org/wiki/Optical_proximity_correction In addition to diffraction and phase shift patterns, you can create shapes by illuminating the mask and wafer with more than one light source. It may be helpful to consider this "multiple illumination" of a single photo mask in the context of a "double slit" interference pattern: https://en.m.wikipedia.org/wiki/Diffraction_from_slits#Multiple_slits https://en.m.wikipedia.org/wiki/Diffraction_from_slits#Multi... After you've run out of tricks, you have write over the shapes laid down by a single mask, running the wafer through the process with a different mask. I find the current Wikipedia article for multi-patterning to be a bit more difficult to understand, but it's certainly worth the effort. After studying this article a bit, I think it might help to start in the middle of the article, at "Pitch Splitting". A second read of the article, starting at the top, may then provide more context: https://en.wikipedia.org/wiki/Multiple_patterning#Pitch_splitting https://en.wikipedia.org/wiki/Multiple_patterning#Pitch_spli... . (Ironic: the article on Multiple Patterning requires multiple passes!)