researching "lithography"

Erik15

I've been researching "lithography" and have been looking for some info on the evolution of various techniques that have improved this process over the last 20 years. Anybody have some knowledge on this? (In relation to Moore's laws).

EtherealPanMan

Given CD= k*(λ/NA), where CD is critical dimension (overall resolution essentially), λ= wavelength of light and NA is numerical aperture,

Well, one aspect of litho that has improved resolution has been simply to increase the energy (ie decrease wavelength) of light during exposure. This requires resist chemists to change their product to suit different energies.

Relatively recently, immersion litho started. This physically puts the wafer in water to decrease the NA during exposure.

EUV is the proposed next gen of light litho (13.5 nm vs current 193 nm light). Unfortunately, it is not so simple as just decreasing the wavelength of light. This has introduced a multitude of other issues that are being worked on in order to get the desired resolutions.

Are there any specific questions?
Cheers!